critical thinking six sigma

Critical Thinking

Critical thinking is more than just a popular term in education and work. It is a key skill that helps people understand the modern world clearly and logically. At its heart, critical thinking means carefully analyzing information, checking if it is true and relevant, and making well-founded decisions.

Today, with so much information coming from many sources and often conflicting views, mastering critical thinking is crucial for making informed choices. It is also essential for solving difficult problems and participating in meaningful discussions and debates.

Table of contents

Definition of critical thinking, key elements of critical thinking, opportunities, final words, related articles.

Critical thinking begins with a mindset that values clarity, precision, evidence and reasoned judgment. It requires individuals to go beyond surface-level understanding and actively engage with information. This engagement involves:

• Analyzing Information : Critical thinkers meticulously analyze information from various sources, including texts, data, visuals, and personal experiences. They scrutinize sources’ reliability, credibility, and bias to discern factual accuracy and relevance.
• Evaluating Arguments : They identify and evaluate arguments presented in discussions or debates. This involves assessing the logic, evidence, and underlying assumptions of each argument to determine its strength and validity.
• Considering Multiple Perspectives : Critical thinkers acknowledge and consider different viewpoints, even those that contradict their own beliefs. They understand that complex issues often have multiple facets and interpretations, requiring a nuanced understanding.
• Making Informed Judgments : Based on their analysis and evaluation, critical thinkers draw reasoned conclusions. They make decisions that are supported by evidence and logical reasoning. They avoid rash judgments or decisions based on emotions or superficial understanding.

To effectively practice critical thinking, individuals develop and apply several key elements:

• Clarity and Precision : They strive to communicate clearly and precisely, using language that accurately conveys their thoughts and reasoning.
• Logical Reasoning : They employ logical reasoning to connect ideas, identify patterns, and draw logical conclusions from available evidence.
• Evidence-Based Analysis : They prioritize evidence over conjecture or anecdotal evidence, ensuring that their conclusions are grounded in factual information.
• Open-Mindedness : Critical thinkers maintain an open mind and are willing to consider alternative viewpoints. They also revise their own beliefs in light of new evidence or persuasive arguments.
• Intellectual Integrity : They uphold intellectual integrity by avoiding biases, fallacies, and emotional reasoning. This ensures the reliability and validity of their conclusions.

Applications of Critical Thinking

Critical thinking is not confined to academic or professional settings but is applicable in various aspects of everyday life:

• Decision Making : It enables individuals to make informed decisions about personal finances, health care options, career choices, and relationships. This is achieved by weighing the pros and cons and evaluating available information.
• Problem Solving : Critical thinkers excel in identifying and analyzing problems. They explore multiple solutions and select the most effective course of action based on logical criteria.
• Media Literacy : In an age of digital information overload, critical thinking helps individuals discern credible sources from misinformation or propaganda. This fosters media literacy and informed citizenship.
• Effective Communication : It enhances communication skills by enabling individuals to articulate their thoughts clearly, support their arguments with evidence, and engage in constructive dialogue with others.

While critical thinking offers numerous benefits, it also presents challenges:

• Cognitive Effort : Engaging in critical thinking requires cognitive effort and mental discipline. This can be challenging amid distractions or when faced with complex or ambiguous information.
• Resistance to Change : Individuals may resist questioning their beliefs or assumptions, preferring comfort over the discomfort of cognitive dissonance that critical thinking sometimes entails.
• Cultural and Contextual Differences : Critical thinking practices may vary across cultures and contexts, influenced by educational systems, societal norms, and ideological perspectives.
• Continuous Improvement : Practicing critical thinking fosters intellectual curiosity, adaptability, and a willingness to learn and grow intellectually.
• Empowerment : It empowers individuals to navigate uncertainty, make well-informed choices, and advocate for themselves and others in various personal, professional, and societal contexts.

Critical thinking is an indispensable skill that equips individuals with the tools to navigate an increasingly complex and interconnected world.

By cultivating clarity, logic, and intellectual rigour, individuals can make informed decisions, solve problems effectively, and contribute meaningfully to their communities and professions. Embracing critical thinking not only enhances personal and professional success but also promotes a culture of reasoned discourse, informed citizenship, and lifelong learning.

• Attribute Data
• What is Lean Thinking: Principles, Benefits & More
• What is the Difference Between Lean and Six Sigma?
• What is Design Thinking?
• Value-Added

Popular Articles:

• What is LEAN?
• What Is Six Sigma?
• What is a Green Belt?
• What is a Black Belt?
• What is a Yellow Belt?
• What is a White Belt?
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• What is a Value Stream Map?

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Six Sigma: The Definitive Guide

What is Six Sigma

Six Sigma (6σ, 6 sigma) is a data-driven and customer-focused approach to improving the quality and efficiency of business processes. It aims to reduce variation and defects in products or services and to achieve near-perfection in meeting customer expectations.

Six Sigma was developed by Motorola in the 1980s and popularized by General Electric in the 1990s. Since then, it has been adopted by many organizations across various sectors and domains.

The overarching premise of Six Sigma is that variation in a process leads to opportunities for error which then leads to risks for product defects. Product defects, whether in a tangible process or a service, lead to poor customer satisfaction. By working to reduce variation and opportunities for error, the Six Sigma method aims to reduce process costs and increase customer satisfaction.

When applied to business processes, Six Sigma allows companies to drastically improve their bottom line by designing and monitoring everyday business activities in ways that minimize waste and resources while increasing customer satisfaction.

Six Sigma and Statistics

At the most basic definition, Six Sigma is a statistical representation of what many experts call a “perfect” process. [1]

Technically, in a Six Sigma process, there are only 3.4 defects per million opportunities. In percentage terms, it implies that 99.99966 percent of the products from a Six Sigma process are without defects.

Six Sigma is both a methodology for process improvement and a statistical concept

that seeks to define the variation inherent in any process.

Importance of Six Sigma

According to the ATO Fact Book, the US Federal Aviation Administration’s air traffic management system handled a total of 15,416,640 flights in FY2022. [2] The table below shows the defect occurrence per million for various σ levels:

Based on a 5σ air traffic control process, errors of some type would have occurred in the process of handling approximately 3,592 flights in FY2022. With a 6σ process, that risk drops to 52.42 errors!

While most people accept a 99.9 percent (5σ) accuracy rate in even the most critical services on a daily basis, the above examples highlight how wide the gap between Six Sigma and Five Sigma really is.

For organizations, it’s not just about the error rate, it’s also about the costs associated with each error.

Consider the example of Amazon which shipped an estimated 7.7 billion packages globally in 2021 amounting to about $470 billion in sales. [3] If each erroneous order costs the company an average of $20 (a very conservative number), the cost of error for Amazon at various Sigma levels is as below:

The cost difference between a 5σ (99.99% accuracy) and a 6σ would mean over $35 million in annual savings for Amazon. From the above table, it is also evident how a drop in sigma level exponentially increases the cost a company incurs.

Origin of Six Sigma

The roots of statistical process control (SPC), which provide a backbone for Six Sigma methods, began with the development of the normal curve by Carl Friedrich Gauss [4] in the 19th century.

In the early part of the 20th century, SPC received another big boost due to several contributions from Walter Shewhart [5] , an engineer and scholar. Among his numerous contributions, two specifically stand out when speaking of Six Sigma:

First, Shewhart closely related sigma level and quality and showed that three sigma from the mean is the point where a process requires correction. Second, he introduced Control charts, which are a critical component of SPC that lets organizations maintain improved performance after a Six Sigma initiative.

During the same time, W. Edwards Deming [6] introduced the Plan-Do-Check-Act Cycle (PDCA) that stressed the importance of continuous improvement – a core tenet of Six Sigma.

Following World War II, Deming worked as a consultant to Japanese manufacturing companies and planted the ideas and concepts that would soon become the Toyota Production System or Lean Six Sigma.

In the 1980s, Bill Smith [7] moved to Motorola as the company was intensifying its quality initiatives to catch up with Japanese competitors. Bill had been brought in to share Japanese quality methods that he had learned while in the country with Motorola.

It was there that Bill Smith along with Mikel Harry [8] invented the Six Sigma improvement methodology, sharing the concept and theory with the CEO and going on to develop it thereafter.

Motorola registered Six Sigma as a service mark [9] in 1991, and as a trademark in 1993. [10] Six Sigma helped the company realize powerful bottom-line results. Motorola claims to have achieved more than $16 Billion in savings because of its Six Sigma efforts. [11]

Since then, companies as diverse as Allied Signal (now Honeywell), General Electric, Sony, Honda, Maytag, Raytheon, Texas Instruments, Bombardier, Canon, Hitachi, Lockheed Martin, and Polaroid have all adopted Six Sigma.

America’s greatest business leaders such as Larry Bossidy of Allied Signal, and Jack Welch of General Electric Company have praised Six Sigma. General Electric’s implementation of Six Sigma which took five years, reportedly resulted in $12 billion savings. [12]

Common Six Sigma principles

Organizations can impact their Sigma level by integrating the core principles of Six Sigma into leadership styles, process management, and improvement endeavors. These core principles are: [13]

Customer Focused improvement

Companies launching Six Sigma are often shocked to find out how little they understand about their customers. In Six Sigma, customer focus becomes the top priority. The measures of Six Sigma performance begin with the customer with improvements defined by their impact on customer satisfaction and value.

Process-Focused approach

Six Sigma positions the process as the key vehicle of success. From designing products and services to measuring performance to improving efficiency and customer satisfaction, Six Sigma advocates that mastering processes is the way to build a competitive advantage in delivering value to customers.

Data and fact-driven management

Six Sigma promotes the “management by fact” approach. It begins by clarifying what measures are key to gauging business performance and then gathers data and analyzes key variables. Thus, problems can be effectively defined, analyzed, and permanently resolved.

At a more down-to-earth level, Six Sigma helps managers answer two essential questions to support data-driven decisions and solutions.

• What data/information do we really need?
• How do we use that data/information to maximum benefit?

Proactive management

Six Sigma encompasses tools and practices that replace reactive habits with a dynamic, responsive, and proactive style of management. By defining ambitious goals that are reviewed frequently, priorities become clear and the focus shifts to problem prevention rather than firefighting and questioning. This often becomes a starting point for creativity and effective change.

Boundaryless collaboration

Six Sigma promotes boundarylessness collaboration that breaks down across organizational lines to improve teamwork. This unlocks opportunities through improved collaboration among companies, vendors, and customers. Billions of dollars are lost every day because of disconnects and outright competition between groups that should be working for a common cause: providing value to customers.

Drive for perfection and tolerate failure

A company that makes Six Sigma its goal will have to keep pushing to be ever more perfect while being willing to accept and manage occasional setbacks. Six Sigma techniques that improve performance also include risk management tools that limit the downside of setbacks or failures. No company will get even close to Six Sigma without launching new ideas and approaches that always involve some risk.

The Six Sigma problem-solving process: DMAIC and DMADV

Six Sigma projects that are meant to improve an existing process follow a roadmap for success known as the DMAIC process (pronounced duh-MAY-ick).

DMAIC is broken into five phases: Define, Measure, Analyze, Improve, and Control. The main activities of a DMAIC project include identifying the critical inputs or causes that are creating the problem, verifying those causes, brainstorming and selecting solutions, implementing solutions, and creating a control plan to ensure the improved state is maintained.

In some cases, teams realize that fixing an existing process may not achieve sustained improvement, instead, a process might need to be completely redesigned. In such cases, teams employ the DMADV method.

DMADV stands for Define, Measure, Analyze, Design, and Verify. The principles governing the method are similar to DMAIC, but the last two phases are geared toward rolling out and testing a completely new process.

In DMAIC define phase, the project requirements are identified, and goals for success are set. Requirements and goal setting might relate to a variety of factors and are dependent on guidance from the leadership and expected budgets.

In a DMADV project, the define phase is more rigid. The teams must also define customer requirements to create a measuring stick to which the process development can be compared.

In both DMAIC and DMADV, teams create a project charter and a basic work plan. A charter is a synopsis of the project and provides common information and a summary of what the team hopes to accomplish. The charter also features a list of team members, names of those responsible for outcomes, a problem statement, a goal, and some basic definitions of scope and metrics for success.

Tools like the SIPOC diagram and Stakeholder Analysis(discussed later) can be used to understand processes and key stakeholders.

The bulk of the measure phase in DMAIC is occupied with gathering data and formatting it in a way that can be analyzed. Teams build tools to capture data, create queries for digital data, sift through enormous amounts of data to find relevant information or capture data by hand in some manual process.

The Measure stage validates assumptions from the Define stage with actual data. It might be required to revisit problem statements, goals, and other process-related definitions. The define stage creates a “rough draft” while the measure converts that into a final one.

In DMADV, the approach is similar, but activities are typically more targeted. Teams collect data and measurements that help define performance requirements for the new process.

Deciding what to measure can be challenging and requires strong observation skills, an understanding of the reasons behind the measure, knowledge of data types such as discrete and continuous, tools for measurement assessment, and a strong background in statistical analysis.

In the Analyze phase of DMAIC, hypotheses are developed about causal relationships between inputs and outputs. Causations are narrowed down to the vital few using methods such as the Pareto analysis (discussed later). Using statistical analysis and data, hypotheses and assumptions are validated.

In a DMAIC project, Analyze phase tends to flow into the Improve phase. Hypothesis testing, assumption validation and possible solutions might begin in Analyze and continue into the Improve phase.

Likewise, in a DMADV project, teams also identify cause-and-effect relationships, but they are more concerned with identifying best practices and benchmarks by which to measure and design the new process.

Teams begin the process design work by identifying value-added and non-value-added activities, locating areas where bottlenecks or errors are likely, and refining requirements to meet the needs and goals of the project.

The lines between Measure and Analyze are often blurrier than the lines between Define and Measure. In some cases, a team must measure, analyze, and then measure some more, particularly if metrics aren’t already in place for a process.

During the Analyze phase, teams use a variety of tools like Pareto Charts, Run Charts, Histograms, Cause-And-Effect Diagrams, Scatter Diagrams, Process Maps, and Value Analysis (all of which are discussed later).

Improve or Design

Six Sigma teams start developing the ideas that began in the Analyze phase during the Improve phase of a project by using statistics and real-world observation to test hypotheses and solutions.

Solutions are standardized in preparation for rolling improved processes to daily production and non-team employees. Teams also start measuring results and laying the foundation for controls that will be built in the last phase.

In the Improve phase, the DMADV project begins to diverge substantially. New processes are designed, which does involve some solutions testing (as in DMAIC), but also mapping workflow principles and actively building new infrastructures.

This might mean putting new equipment in place, hiring and training new employees, or developing new software tools.

As solutions are narrowed down, more than one might appear compelling and it can get challenging to determine which of the solutions improve a process. In such cases, changes are implemented one at a time and verified before moving on to the next.

Tools like the Solutions Selection Matrix (discussed later) can be used to evaluate and choose the best solutions.

Control or Verify

Control/Verify phase is where loose ends are tied and the project is transitioned to a daily work environment. Controls and standards are established so that improvements can be maintained and the responsibility for those improvements is transitioned to the process owner.

In DMAIC, teams usually handle four tasks:

• creating the foundation for process discipline
• finalizing documents related to the improvement
• establishing ongoing metrics to evaluate the process
• and building a process management plan that lets the team transition the improvement to the process owner.

Tools during the Control phase include documentation checklists, control charts, response plans, process maps, and process dashboards.

Verify phase of DMADV is like the Control phase, but with the exception that teams might perform further critical-to-quality (CTQ) analysis (discussed later) at the end of a project to identify new CTQ factors.

This is essential as the process/product could be different from when the team started working. At the end of the Verify phase, the final product or a process that meets the needs first identified in the Define stage is delivered.

When to use DMAIC and DMADV?

Why are the DMAIC and DMADV models effective?

The DMAIC/DMADV model provides seven key advantages:

• Measuring the problem: In DMAIC, teams just don’t assume that they understand the problem, they are required to prove (validate) it with facts.
• Focus on the customer: The process always considers the external customer’s interests which is important, especially when an organization is trying to cut costs in a process.
• Verifying root cause: Teams agreeing on a cause is not proof enough. Teams must prove their cause with facts and data.
• Breaking old habits: DMAIC/DMADV projects have proven to go beyond minor changes in crusty old processes and drive real change and results through creative new solutions.
• Managing risks: Testing and perfecting solutions is embedded within the process which mitigates risks.
• Measuring results: Solutions and their impact are verified through facts with goals and metrics clearly defined.
• Sustaining change: Even the best of new “best practices” developed by a DMAIC team can die quickly if not nurtured and supported. Making change is the final key and part of this problem-solving approach.

The Six Sigma toolkit

Any technique that helps better understand, manage, and improve a business or a process can qualify as a Six Sigma tool, but some of them are key to planning and executing Six Sigma projects.

Understanding these tools gives a clearer perspective on how Six Sigma works. These tools are bunched into four categories:

Tools for generating ideas and organizing information

Tools for data gathering, tools for process and data analysis, tools for statistical analysis.

The goal of this article is to provide a quick overview of each of these tools. More details and how-to information can be found in a variety of other books and websites.

1. Brainstorming

Many Six Sigma methods have brainstorming, or idea generation, as a starting point. Brainstorming is an idea-creation method for generating many creative ideas in a short period. Brainstorming can be used when:

• A broad range of options is to be generated
• Creative, original ideas are required
• Group participation is desired

During a brainstorming session, all ideas are to be treated as valid and worthy of consideration. At this stage, ideas are not criticized or evaluated. They are to be recorded as-is without discussion. Even combining, modifying, and expanding on others’ ideas is encouraged.

Methods like the “Sticky Storm Technique” [14] that combines individual and group brainstorming can be used.

2. Affinity Diagramming

The Affinity Diagram [15] (also known as Affinity Chart, Affinity Mapping, K-J Method, or Thematic Analysis) groups ideas according to their natural relationships. It usually follows the brainstorming stage to help organize the output.

It can be used to organize and consolidate information related to a product, process, complex issue, or problem. Ideas are grouped according to their affinity or similarity.

Teams creating affinity diagrams record each idea on a note or a card. They then look for relationships between individual ideas and have team members simultaneously sort the ideas into five to ten related groupings. The process is repeated until all ideas are grouped.

It is okay to have “loners” that don’t seem to fit a group. It is also okay to move a note someone else has already moved. If a note seems to belong to two groups, a second note can be made.

It is important to avoid talking during this process. The focus should be on looking for and grouping related ideas without attaching any priority or importance to them.

3. Multivoting

Multivoting [16] narrows a large list of possibilities to a smaller list of top priorities. Each participant gets a certain number of votes (unlike a single vote in straight voting). This allows an item that is favored by all, but not the top choice of any, to rise to the top.

Multivoting can be used:

• After brainstorming generates a long list of possibilities
• When a list must be narrowed down
• When a decision must be made by group judgment

4. Structure Tree (Tree Diagram)

A Structure Tree [17] (also known as Systematic Diagram, Tree Analysis, Analytical Tree, or Hierarchy Diagram) is used to depict the hierarchy of tasks and subtasks needed to complete an objective.

The tree diagram starts with one item that branches into two or more, each of which branches into two or more, and so on. The finished diagram bears a resemblance to a tree, with a trunk and multiple branches.

As seen from the figure above, a tree diagram breaks down broad categories into finer levels of detail. Developing the tree diagram helps teams to think step by step from generalities to specifics.

A tree diagram can be used when:

• An issue, that is known in broad generalities must move to specific details
• Developing actions to carry out a solution or a plan
• Analyzing processes in detail
• Probing for the root cause of a problem
• Evaluating implementation issues for several potential solutions
• After an affinity diagram or interrelationship diagram has uncovered key issues
• As a communication tool, to explain details to others

5. High-level process map (SIPOC diagram)

SIPOC [19] (pronounced “sye-pahk”) is an acronym for Supplier, Input, Process, Output, Customer. SIPOC is used in the Define phase of DMAIC and is often a preferred method for diagramming major business processes and identifying possible measures.

SIPOC shows the major activities or sub-processes in a business in a systematic framework represented by the Suppliers, Inputs, Processes, Outputs, and Customers. This helps identify the boundaries and critical elements of a process without losing sight of the big picture.

In a SIPOC diagram, suppliers are the sources for the process, inputs are the resources needed for the process to function, the process constitutes the high-level steps that the system/organization undertakes, outputs are the results of those processes and customers are the people who receive outputs or benefit from the process.

Creating a SIPOC diagram helps answer the following questions:

• How can a process be made easier?
• Is a quality product delivered to the customers?
• Can supplier management be improved?
• Are suppliers delivering as per need?
• Are the customer persona and the demographics they fall into known?
• Are there any inefficiencies that can improve when creating the product?

Sometimes, a variation of the SPCIF diagram called SIPOC+CM [21] is used that also maps the Constraints (C) and the Measures (M).

6. Flowchart

A Flowchart [22] is used to show details of a process, including tasks and procedures, alternative paths, decision points, and rework loops. While simple flowcharts can be constructed with a bunch of stickies on a wall, complex ones are developed using advanced software [23] that offers extensive capabilities.

A flowchart is a visual representation of distinct steps of a process in sequential order. Elements that may be included in a flowchart are a sequence of actions, materials or services entering or leaving the process (inputs and outputs), decisions that must be made, people who become involved, time involved at each step, and/or process measurements.

Flowcharts can be used:

• To develop an understanding of how a process is done
• To study a process for improvement
• To communicate to others how a process is done
• For better communication among people involved with the same process
• To document a process
• When planning a project

7. Fishbone diagram

A Fishbone diagram [25] (also known as Cause-And-Effect Diagram, Ishikawa Diagram) is used to brainstorm possible causes of a problem (or effect) and puts the possible causes into groups or affinities. Causes that lead to other causes are linked similarly to a structure tree.

The fishbone diagram helps gather collective ideas from the team on where a problem might arise and enables the team members to think of all possible causes by clarifying major categories.

While a fishbone diagram does not reveal the right cause, it helps develop educated guesses, or hypotheses, about where to focus measurement and further root cause analysis.

A fishbone diagram can be used:

• When identifying possible causes for a problem
• When a team’s thinking tends to diverge

8. Critical to Quality (CTQ) tree

A CTQ tree [27] is a visual tool to identify and prioritize the critical quality characteristics (CTQs) that are most important to customers. It helps map the relationship between customer requirements and specific product or process characteristics for improvement focus.

A CTQ tree starts by identifying the customer needs and then branches into drivers and requirements. Building a CTQ tree requires identifying:

• The Need: This is the actual product or service that a customer wants.
• The Drivers: These are quality drivers that must be present to fulfil customer needs.
• The Requirements: These are the list of the requirements for each driver. In other words, recording measurable performance metrics for each driver.

In Six Sigma, once an organization has completed the Voice of Customer (VOC) process, it is useful to build a CTQ tree to:

• Bring more clarity in understanding customer needs
• Identifying current issues and improving the product or service
• Help design or develop a product or service during the early stages of the process
• Stand out from competitors

1. Sampling

Sampling [28] is the selection of a set of elements from a target population or product lot. Sampling is used frequently as gathering data on every member of a target population or every product is often impossible, impractical, or too costly.

Sampling helps draw conclusions or make inferences about the population or product lot from which the sample is drawn.

When used in conjunction with randomization [29] (randomly selecting factors, measurements, or variables to eliminate the effects of bias or chance), samples provide virtually identical characteristics relative to those of the population or product grouping from which the sample was drawn.

Teams must be careful to avoid sampling errors which are primarily of three kinds:

• Bias (lack of accuracy)
• Dispersion (lack of precision)
• Non-reproducibility (lack of consistency)

2. Operational Definitions

An Operational Definition [30] is a clearly defined description of some characteristic. It should be specific and describe not only what is being measured but how. An operational definition needs to be agreed upon by all parties, whether that is a customer or an internal function of the organization.

For example, an Amazon search for “blue shirt” will yield the following result:

This is the key purpose of an operational definition. Everyone must define, measure, and interpret things the same way.

3. Voice Of The Customer (VOC) Methods

Voice Of the Customer (VOC) [31] is the direct input and expression of the wants, needs, and expectations that the customer has for the organization with which the customer conducts business.

In Six Sigma, VOC is the structured process of directly soliciting and gathering the specifically stated needs, wants, expectations and performance experiences of the customer about the products and/or services that an organization provides.

There are several ways an organization can capture the VOC, such as:

• Direct observations
• Focus groups
• Complaint data
• Customer service reps
• Existing company data
• Industry data

Unintended miscommunication between an organization and its customers is a common reason why organizations lose customers and their business. It is critical for an organization to understand the VOC and customer requirements.

4. Checksheets

A Checksheet [33] (also called a defect concentration diagram) is a structured, prepared form for collecting and analyzing data. It is a generic data collection and analysis tool that can be adapted for a wide variety of purposes and is considered one of the seven basic quality tools.

A checksheet can be used when:

• Data can be observed and collected repeatedly by the same person or at the same location.
• Collecting data on the frequency or patterns of events, problems, defects, defect location, defect causes, or similar issues.
• Collecting data from a production process.

Checklists have two key objectives:

• Ensure that the right data is captured, with all necessary facts included, such as when it happened, how many, and what customer. These facts are called stratification factors. [32]
• To make data gathering as easy as possible for the collectors.

Checksheets can vary from simple tables and surveys to diagrams used to indicate where errors or damage occurred. Spreadsheets are the place where checksheet data is collected and organized. A well-designed spreadsheet makes it much easier to use the data.

5. Measurement Systems Analysis (MSA)

A measurement systems analysis (MSA) [34] is an umbrella term covering various methods used to ensure that measures are accurate and reliable. MSA evaluates the test method, measuring instruments, and the entire process of obtaining measurements to ensure the integrity of data used for analysis and to understand the implications of measurement error for decisions made about a product or process.

An MSA considers the following:

• Selecting the correct measurement and approach
• Assessing the measuring device
• Assessing procedures and operators
• Assessing any measurement interactions
• Calculating the measurement uncertainty of individual measurement devices and/or measurement systems

Common tools and techniques of measurement systems analysis include calibration studies, fixed effect ANOVA [35] , components of variance, attribute gage study, gage R&R, ANOVA gage R&R [36] , and destructive testing analysis.

The goals of MSA are:

• Quantification of measurement uncertainty, including the accuracy, precision, repeatability, reproducibility, and discrimination
• Quantifying the stability and linearity of these quantities over time and across the intended range of use of the measurement process.
• Development of improvement plans, when needed.
• Deciding if a measurement process is adequate for a specific engineering or manufacturing application.

Checking on people performing the measurements is also a part of MSA.

1. Process-Flow Analysis

A process flow analysis uses the process map or a flowchart as input to scrutinize the process for redundancies, unclear hand-offs, unnecessary decision points, and so on. Process data can reveal problems such as delays, bottlenecks, defects, and rework.

A process flow analysis can be one of the quickest ways to find clues about the root causes of problems.

2. Value and Non-Value-Added Analysis

Activities usually fall under three kinds:

• Value-added activities
• Non-value-added activities
• Business value-added activities

Value-added activities are those activities for which the customer is willing to pay for and non-value-added activities are those for which the customer is not willing to pay.

Business value-added activities are those for which the customer is not willing to pay but are necessary for the running of processes and the business. These could include work performed for audits, controls, risk management, regulatory requirements, etc.

In Six Sigma, both non-value-added and business value-added activities are considered “wastes” but are segregated and treated differently.

Wastes can be identified using the following questions:

• Does the activity transform the form, feature, feeling and function that the customer is willing to pay for?
• Is it being done right the first time?
• Is this something the customer expects to pay for?

A positive answer or a “yes” to all of them indicates that it is a value-added activity. Even a single “No” indicates that it is either a non-value-added activity or a business value-added activity.

It’s never possible to eliminate all non-value-adding activities, especially Business value-added activities, But this approach helps in reducing the non-essential aspects of a process that are a drain on resources.

3. Charts and Graphs:

The first and best way to analyze measures of a process is to create a picture of the data and charts and graphs help accomplish just that. Visual representation of data becomes a lot more meaningful and convenient to read than a table of numbers.

Charts and graphs help make discoveries that the numbers themselves would hide. Charts and graphs are of various types, each offering a bit different picture of the data.

Following are some of the most used types of charts and graphs:

Pareto Chart

A Pareto is a specialized bar chart that breaks down a group by categories and compares them from largest to smallest. It’s used to look for the biggest pieces of a problem or contributors to a cause. Learn more about Pareto analysis .

Histogram (Frequency Plot)

A histogram is a type of bar chart that shows the distribution or variation of data over a range: size, age, cost, length of time, weight, and so on. (A Pareto chart, by contrast, slices data by category)

In analyzing histograms, teams can look for the shape of the bars or the curve, the width of the spread, or range, from top to bottom, or the number of “humps” in the bars. When customer requirements are plotted on a histogram, it reveals how much what’s being done meets or does not meet customers’ needs.

Run (Trend) Chart

Pareto charts and histograms don’t reveal the time dimension, i.e. how things change over time. A run chart accomplishes just that.

Consider the below example of a chemical process that is sensitive to ambient temperature. It can be visually inferred that the temperatures during the months of April through July have a negative bearing on the process leading to defects.

Control Chart

A control chart is also used to study how a process changes over time. Data are plotted in time order. But unlike a Run Chart, a Control Chart always has a central line for the average, an upper line for the Upper Control Limit (UCL), and a lower line for the Lower Control Limit (LCL). These lines are determined from historical data.

Any data point falling between the UCL and the LCL is considered as safe. The data points falling outside the LCL and the UCL are called ‘Outliers’. All outliers are candidates for Root Cause Analysis.

Control charts are used for:

• Controlling ongoing processes by finding and correcting problems as they occur
• Predicting the expected range of outcomes from a process
• Determining whether a process is stable (in statistical control)
• Analyzing patterns of process variation from special causes (non-routine events) or common causes (built into the process)
• Determining whether a quality improvement project should aim to prevent specific problems or to make fundamental changes to the process

Scatter Plot (Correlation) Diagram

A Scatter plot looks for direct relationships between two factors in a process, usually to see whether they are correlated, meaning that a change in one is linked to a change in the other.

When an increase in one factor matches an increase in the other, it’s a “positive correlation” and likewise the reverse is a “negative correlation”. If two measures show a relationship, one may be causing the other.

However, a correlation does not necessarily mean causation. The underlying connection may be hidden. For example, there is a statistical correlation between eating ice cream and drowning incidents, but ice cream consumption does not cause drowning. They are connected by a third common cause which is warm summer weather.

A scatter plot helps a DMAIC team visualize the relationship between process output (Y) and suspected cause/input factors (X). As a practice, X is plotted on the horizontal axis (independent variable), while Y is plotted on the vertical axis (dependent variable).

In some cases, collected data is not accurate enough. Analysis of such data requires a level of proof beyond what visual tools can offer. Six Sigma teams apply more sophisticated statistical analysis tools in such cases.

The statistical part of the toolkit contains many different tools and formulas. Some of the broad families of statistical methods are:

Tests of statistical significance

These tools look for differences in groups of data to see whether they are meaningful. These tests include Chi-square, t-tests, and analysis of variance. [39]

Correlation and regression

These tools are similar to a scatter plot but can get a lot more complex, including regression coefficients, simple linear regression, multiple regression, surface response tests, and so on. These tools test for the presence, strength, and nature of the links among variables in a process or a product, such as how tire pressure, temperature, and speed would affect gas mileage. [40]

Design Of Experiments (DOE)

DOE deals with planning, conducting, analyzing, and interpreting controlled tests to evaluate the factors that control the value of a parameter or group of parameters. DOE is a powerful data collection and analysis tool that can be used in a variety of experimental situations.

It allows for multiple input factors to be manipulated, determining their effect on a desired output (response). DOE can identify important interactions that may be missed when experimenting with one factor at a time.[ 41]

Tools for implementation and process management

1. project management methods.

Six Sigma companies recognize early on the importance of strong project management skills: planning, budgeting, scheduling, communication, and people management. Technical project management tools such as Gantt chart scheduling can be used for implementation and process management.

2. Potential Problem Analysis (PPA) and Failure Mode and Effects Analysis (FMEA)

PPA is a systematic method for determining what could go wrong in a plan under development. The problem causes are rated according to their likelihood of occurrence and the severity of their consequences. Preventive actions are taken, and contingency plans are developed. The process helps to create a smooth, streamlined implementation process. [42]

Similarly, FMEA is a step-by-step approach for identifying all possible failures in a design, a manufacturing or assembly process, or a product or service. It is a common process analysis tool. FMEA begins during the earliest conceptual stages of design and continues throughout the life of the product or service. [43]

3. Stakeholder Analysis

Complex change can affect a lot of people. Six Sigma teams recognize that for change to be successful, it is important to consider the needs and perspectives of various parties involved, i.e. the stakeholders.

The Stakeholder Analysis [44] process is used to determine who the stakeholders are, what are their wants, goals, and concerns and how best to understand mutual interests.

Stakeholders are grouped based on their interest in the project outcome and the power they hold in influencing the change. They usually fall under four categories, each of which needs a different approach to drive successful change:

4. Force Field Diagram

A Force Field Diagram is a result of a force field analysis that shows the relationship between factors that help promote a change vs. those that oppose or create resistance. Like stakeholder analysis, the force field is used to develop plans to build support for a critical change.

A force field diagram helps the team to focus on improving the driving forces and weakening the resisting forces through education or refinements.

5. Balanced Scorecards

The balanced scorecard [45] is a strategic management tool that views the organization from different perspectives, usually the following:

• Financial: The perspective of shareholders
• Customer: How customers experience and perceive an organization
• Business process: Key processes used to meet and exceed customer/shareholder needs
• Learning and growth: How to foster ongoing change and continuous improvement

A balanced scorecard provides feedback on both internal business processes and external outcomes to continuously improve strategic performance and results.

6. Solution Selection Matrix

A Solution Selection Matrix (SSM), also known as a Decision Matrix or a Criteria Matrix, is a tool used to objectively assess the strengths and weaknesses of each option and determine the best course of action.

SSM consists of a table or a grid of options and criteria. Each criterion represents a specific aspect or attribute that is important in evaluating the options. The evaluator assigns a rating or score to each option for each criterion.

Once the ratings are assigned, they are often weighted (by assigning a numerical value) to indicate the relative importance. A weighted score is then calculated for each option by multiplying the rating by the corresponding weight.

The option with the highest overall score indicates the most favorable choice. SSM provides a structured and systematic approach to decision-making, helping to eliminate bias and subjectivity.

7. Process Dashboards

A Process Dashboard is a vital decision management tool that showcases essential information about process performance to process participants and owners. It provides high-maturity, metrics-intensive data necessary for process analysis and decision-making.

8. Process Documentation

As a DMAIC project reaches a conclusion with solutions in place and results in hand, the Six Sigma team must turn over responsibility to those who will manage the process on an ongoing basis.

Creating effective, clear, not overly complex process documentation that includes process maps, task instructions, measures, and more is the last and most important element of the DMAIC Control step.

Note on Six Sigma tools

While Six Sigma is rich with tools that help make better decisions, solve problems, and manage change, Six Sigma and the tools are one and the same.

Using too many tools can complicate things. Demanding that they be used when they aren’t helpful can undermine the goals of Six Sigma just as easily as not using tools.

The following are important considerations when selecting a Six Sigma tool:

• Use only the tools that help in getting the job done.
• Keep it as simple as possible.
• When a tool isn’t helping, stop and try something else.

Six Sigma breakthrough equation

Six Sigma looks at every process through what is known as the breakthrough equation shown below:

• Y is the outcome(s) or result(s) desired or needed.
• X represents the inputs, factors, or pieces necessary to create the outcome(s). There can be more than one Xs.
• ƒ is the function, the way or process by which the inputs are transformed into the outcome.
• ε (epsilon) is the presence of error or uncertainty surrounding how accurately the Xs are transformed to create the outcome.

In any process, a set of input variables are transformed by a function (or process) and combined with error to form the output. The Y results from, or is a function of, the Xs.

In the bread-making example above, bread is the Y (output). Inputs like the dough, salt, yeast etc., are the Xs while the process of dough making and baking are the ƒ. Errors like wrong temperature leading to improper baking represent the epsilon (ε).

Basic Metrics in Six Sigma

When applying Six Sigma to processes and improvements, the below metrics are used to access and measure process accuracy levels:

Defects Per Unit (DPU)

DPU is a measure of how many defects there are in relation to the number of units tested.

It is concerned with total defects, and one unit could have more than one defect.

For example, if a publisher printed 1,000 books and pulled out 50 books for quality checks,

that revealed:

• 3 books are missing pages
• 1 book is missing pages and has a torn cover
• 2 books have loose spines
• 1 book has incorrect printing and incorrect alignment

There are 9 total errors in a sample size of 50 books, hence the DPU is calculated as:

DPU provides an average level of quality. It tells how many defects on average each unit can be expected to have. In this case, that is 0.18 defects on average.

Defects per Opportunity (DPO)

DPO is the number of defects in a sample divided by the total number of defect opportunities.

In the above example, each book has a possibility of 5 types of errors (missing page, torn cover, loose spine, incorrect printing, and incorrect alignment). Hence the opportunity for error in each book is 5 and DPO is calculated as:

Defects per Million Opportunities (DPMO)

This represents a ratio of the number of defects in one million opportunities. In other words, how many times did a flaw or mistake (defect) occur for every million opportunities there were to have a flaw or a mistake?

DPMO is also the same as DPO multiplied by a million. By scaling the sample size to a common value (1 million), DPMO allows to compare accuracy levels of different processes.

In the book example, DPMO is calculated as:

First-Time Yield (FTY)

FTY is the ratio of units produced to units attempted to produce.

For example, if 100 cookies were put in the oven, but only 95 came out edible, then:

Most products or services are created via multiple processes, in which case FTY for each process needs to be multiplied to calculate an overall FTY.

Rolled Throughput Yield (RTY)

RTY provides a probability that a unit will be generated by a process with no defects.

One of the main differences between RTY and FTY is that RTY considers whether rework was needed to generate the number of final units. This is valuable as organizations don’t always think about the rework that is inherent in a process, which means they often measure a process and deem it successful even if waste is present.

Consider the following process chain:

The RTY is calculated as follows:

RTY for Process A: 100 – (5 + 5) = 90, 90/100 = 0.9

RTY for Process B: 95 – (10 + 5) = 80, 80/95 = 0.84

RTY for Process C: 85 – (5 + 15) = 65, 65/85 = 0.76

Overall RTY = 0.9 * 0.84 * 0.76 = 0.574

While RTY does not indicate final production or sales, a low RTY indicates that there is waste in the process in the form of rework.

Six Sigma vs. Lean Six Sigma

While Six Sigma focuses on eliminating defects and reducing variation, Lean Six Sigma (LSS) focuses on eliminating waste and improving speed. LSS combines Lean Management and Six Sigma to increase the velocity of value creation.

During the 2000s, Lean Six Sigma forked from Six Sigma and became its own unique process. LSS developed as a specific process of Six Sigma, incorporating ideas from lean manufacturing, which was developed as a part of the Toyota Production System in the 1950s.

Lean Six Sigma is more specifically used to streamline manufacturing and production processes, while Six Sigma methodologies can benefit any business.

Six Sigma Training Levels and Roles

Possessing a Six Sigma certification proves that an individual has demonstrated practical applications and knowledge of Six Sigma. These certification levels are differentiated by belt level.

The belt color someone holds will help to determine what role they will play in a given project and how they will be spending their time. Broadly they are shown as below:

In addition to the above levels, there is Six Sigma Champion which is not a belt per se but plays a crucial role in Six Sigma projects and organizations.

The primary function of the Champion is to ensure that all operational projects align with strategic business objectives.

1. “Six SIGMA: A Complete Step-By-Step Guide: A Complete Training & Reference Guide for White Belts, Yellow Belts, Green Belts, and Black Belts”. Six Sigma Council, https://www.sixsigmacouncil.org/wp-content/uploads/2018/08/Six-Sigma-A-Complete-Step-by-Step-Guide.pdf . Accessed 06 Jul 2023

2. “Air Traffic By The Numbers”. Fedaral Avaiation Administration, https://www.faa.gov/air_traffic/by_the_numbers . Accessed 06 Jul 2023

3. “How many Amazon packages get delivered each year?”. The Conversation, https://theconversation.com/how-many-amazon-packages-get-delivered-each-year-187587 . Accessed 06 Jul 2023

4. “Carl Friedrich Gauss”. Wikipedia, https://en.wikipedia.org/wiki/Carl_Friedrich_Gauss . Accessed 06 Jul 2023

5. “Walter A Shewhart”. Sixsigmastudyguide, https://sixsigmastudyguide.com/shewhart/ . Accessed 06 Jul 2023

6. “Edwards Deming”. Wikipedia, https://en.wikipedia.org/wiki/W._Edwards_Deming . Accessed 08 Jul 2023

7. “Bill Smith”. Wikipedia, https://en.wikipedia.org/wiki/Bill_Smith_(Motorola_engineer) . Accessed 08 Jul 2023

8. “Mikel Harry”. Wikipedia, https://en.wikipedia.org/wiki/Mikel_Harry . Accessed 08 Jul 2023

9. “Trademark Status & Document Retrieval (TSDR)”. The United States Patent and Trademark Office (USPTO), https://tsdr.uspto.gov/#caseNumber=1647704&caseSearchType=US_APPLICATION&caseType=SERIAL_NO&searchType=statusSearch . Accessed 08 Jul 2023

10. “SIX SIGMA – Trademark Details”. Justia, https://trademarks.justia.com/741/99/six-74199225.html . Accessed 08 Jul 2023

11. “The History of Six Sigma”. Isixsigma, https://www.isixsigma.com/history/history-six-sigma/ . Accessed 08 Jul 2023

12. “Six Sigma Case Study: General Electric”. 6sigma, https://www.6sigma.us/ge/six-sigma-case-study-general-electric/ . Accessed 08 Jul 2023

13. “What Is Six Sigma?”. Peter S. Pande, Lawrence Holpp, https://books.google.co.in/books/about/What_Is_Six_Sigma.html?id=vBzaUJuH8hYC&redir_esc=y . Accessed 10 Sep 2023

14. “BRAINSTORMING”. American Society for Quality, https://asq.org/quality-resources/brainstorming . Accessed 08 Jul 2023

15. “WHAT IS AN AFFINITY DIAGRAM?”. American Society for Quality, https://asq.org/quality-resources/affinity . Accessed 08 Jul 2023

16. “WHAT IS MULTIVOTING?”. American Society for Quality, https://asq.org/quality-resources/multivoting . Accessed 08 Jul 2023

17. “WHAT IS A TREE DIAGRAM?”. American Society for Quality, https://asq.org/quality-resources/tree-diagram . Accessed 08 Jul 2023

18. “Tree Diagram: All you need to know about it”. Qidemy, https://qidemy.com/tree-diagram-all-you-need-to-know-about-it/ . Accessed 08 Jul 2023

19. “What is a SIPOC diagram? 7 steps to map and understand business processes”. Asana, https://asana.com/resources/sipoc-diagram . Accessed 08 Jul 2023

20. “SIPOC”. Wikipedia, https://en.wikipedia.org/wiki/SIPOC . Accessed 08 Jul 2023

21. “SIPOC+CM DIAGRAM”. American Society for Quality, https://asq.org/quality-resources/sipoc . Accessed 08 Jul 2023

22. “WHAT IS A FLOWCHART?”. American Society for Quality, https://asq.org/quality-resources/flowchart . Accessed 08 Jul 2023

23. “Comparison of Business Process Model and Notation modeling tools”. Wikipedia, https://en.wikipedia.org/wiki/Comparison_of_Business_Process_Model_and_Notation_modeling_tools . Accessed 08 Jul 2023

24. “Flowchart”. Wikipedia, https://en.wikipedia.org/wiki/Flowchart . Accessed 09 Jul 2023

25. “FISHBONE DIAGRAM”. American Society for Quality, https://asq.org/quality-resources/fishbone . Accessed 09 Jul 2023

26. “Ishikawa diagram”. Wikipedia, https://en.wikipedia.org/wiki/Ishikawa_diagram . Accessed 09 Jul 2023

27. “Critical to Quality Tree (CTQ)”. Minnesota Department of Health, https://www.health.state.mn.us/communities/practice/resources/phqitoolbox/ctqtree.html . Accessed 10 Jul 2023

28. “WHAT IS SAMPLING?”. American Society for Quality, https://asq.org/quality-resources/sampling . Accessed 11 Jul 2023

29. “Randomization: Key to Reducing Bias and Increasing Accuracy”. Isixsigma, https://www.isixsigma.com/dictionary/randomization/ . Accessed 09 Jul 2023

30. “Operational Definition”. Isixsigma, https://www.isixsigma.com/dictionary/operational-definition/ . Accessed 09 Jul 2023

31. “How to Use Voice of the Customer to Improve Customer Experience”. Isixsigma, https://www.isixsigma.com/dictionary/voice-of-the-customer-voc/ . Accessed 09 Jul 2023

32. “WHAT IS STRATIFICATION?”. American Society for Quality, https://asq.org/quality-resources/stratification . Accessed 09 Jul 2023

33. “CHECK SHEET”. American Society for Quality, https://asq.org/quality-resources/check-sheet . Accessed 11 Jul 2023

34. “Measurement System Analysis (MSA)”. Lean6sigmapro, https://www.lean6sigmapro.com/knowledgebase/msa . Accessed 09 Jul 2023

35. “Distinguishing Between Random and Fixed: Variables, Effects, and Coefficients”. Portland State University, https://web.pdx.edu/~newsomj/mlrclass/ho_randfixd.pdf . Accessed 09 Jul 2023

36. “ANOVA gauge R&R”. Wikipedia, https://en.wikipedia.org/wiki/ANOVA_gauge_R%26R . Accessed 09 Jul 2023

37. “Control Chart”. Project Management Research Institute, https://pmri.in/dictionary/control-chart/ . Accessed 10 Jul 2023

38. “Data Demystified: Correlation vs. Causation”. Datacamp, https://www.datacamp.com/blog/data-demystified-correlation-vs-causation . Accessed 09 Jul 2023

39. “Tests of Statistical Significance”. California State University, Long Beach, https://home.csulb.edu/~msaintg/ppa696/696stsig.htm . Accessed 09 Jul 2023

40. “Statistics review 7: Correlation and regression”. National Library of Medicine , https://www.ncbi.nlm.nih.gov/pmc/articles/PMC374386/ . Accessed 09 Jul 2023

41. “WHAT IS DESIGN OF EXPERIMENTS (DOE)?”. American Society for Quality, https://asq.org/quality-resources/design-of-experiments . Accessed 09 Jul 2023

42. “Potential Problem Analysis”. Digital Healthcare Research, https://digital.ahrq.gov/health-it-tools-and-resources/evaluation-resources/workflow-assessment-health-it-toolkit/all-workflow-tools/potential-problem-analysis . Accessed 09 Jul 2023

43. “FAILURE MODE AND EFFECTS ANALYSIS (FMEA)”. American Society for Quality, https://asq.org/quality-resources/fmea . Accessed 09 Jul 2023

44. “Stakeholder Analysis Process”. Projectmanagement, https://www.projectmanagement.ie/blog/stakeholder-analysis-process/ . Accessed 10 Jul 2023

45. ” The Balanced Score Card”. Shree Phadnis, Master Black Belt at KPMG (India), https://www.symphonytech.com/articles/bscard.htm . Accessed 10 Jul 2023

46. “The Balanced Scorecard—Measures that Drive Performance”. Harvard Business Review, https://hbr.org/1992/01/the-balanced-scorecard-measures-that-drive-performance-2 . Accessed 10 Sep 2023

47. “MANUFACTURING DASHBOARD EXAMPLES”. Datapine, https://www.datapine.com/dashboard-examples-and-templates/manufacturing . Accessed 09 Jul 2023

48. “A comparison between Six Sigma and Lean Six Sigma”. Amileinstitute, https://www.amileinstitute.org/blog/a-comparison-between-six-sigma-and-lean-six-sigma/ . Accessed 10 Jul 2023

49. “What are the Levels (Belts) of Lean Six Sigma Certification?”. Dcmlearning, https://dcmlearning.ie/lean-resources/different-levels-belts-of-lean-six-sigma-certification.html . Accessed 11 Jul 2023

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Lean, Six Sigma + Critical Thinking

Lean-Sigma Expert Brad Wyrick

Brad is a Motorola Business Partner. Here he shares his expert opinion about applying the BPI critical thinking methods to process improvement. Brad and his team are certified BPI instructors.

“Whatever the industry, speed is critical to your business’s competitiveness and health. There are more than 200 process improvement tools for organizations to choose from when looking at problems, opportunities, and growth potential. These tools can help . . . any product, process or service become simpler, smoother, and more stable. Critical thinking tools speed up how people think together and clean up logical gaps between tool sets. Taken together, the critical thinking tools form a framework. The framework is made up of questions designed to facilitate analysis of any situation by defining specific logical needs. This framework is perfect for integrating other tools to fill these logical needs when and if their unique contribution is needed to answer one of the questions.

“BIG THREE: Lean Enterprise tools reduce non-value added activities, create flow throughout the organization and reduce lead times dramatically. Six Sigma tools reduce variation in value added activities, stabilize processes, and build in repeatability. The failure of most process improvement initiatives occurs when organizations are missing Critical Thinking tools. They use a small collection of their favorite tools which often don’t uncover the root cause of the problem or fail to inform them that they simply have a decision to make. Critical Thinking bridges the gap between Reactive and Proactive decision making.

“Incorporating the Critical Thinking Process into your tool box will reduce the time your teams spend on any project. Critical Thinking helps you to analyze the opportunity quickly and points you toward the right tools. Alice-In-Wonderland said, “If you don’t know where you are going, any road will get you there.” The question is; do you have a Problem to solve, a Decision to make, a Planning opportunity or a combination of all three? Spending time up front defining the purpose, focus and process will save you enormous amounts of time and effort down the road.

“Symptoms of the need for improved critical thinking include: difficulty with (or avoidance of) complex issues, long meeting times with complaints of lack of progress or going in circles, frustration when attempting to influence others, and failure to agree or develop optimal, highest quality actions.

“If you are struggling to achieve breakthrough improvements, are uncertain about which improvement approach to adopt – or are relying on traditional TQM tools; we invite you to harness the synergy of Lean and Six Sigma with the speed of Critical Thinking. This will enable you to achieve fast, dramatic improvements in translating abstract desires from the Voice-of-the-Customers into concrete specifications and organizational requirements. Leaders will use this data to transform the strategic goals and processes in a way that delivers value to the end user.

“ Critical Thinking gives people a new and dramatic boost in thinking effectively and efficiently. These new principles offer tangible solutions to drastically cut the percentage of waste and to improve quality, productivity, and profitability. Properly applied, Critical Thinking will provide you a quicker return on investment.”

Brad Wyrick

Former Founder and President Wyrick Enterprises Lean, Six Sigma + Critical Thinking

Business Processes Inc. * R & D * P.O. Box 1456 * La Jolla, CA 92038 www.critical-thinking.com

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Incorporating Critical Thinking into Lean Six Sigma

Reflection is an often-overlooked element of problem solving, social sharing block, add new comment.

T he three value concepts of my new lean Six Sigma model are based on the Chinese terms shin, gunaxi, and zhi . The third term, zhi, means to know or understand. Confucius believed that for most people, learning was ongoing. One of the philosophies of Confucianism is that everything a person learns is subject to evaluation and reflection, and it is through this iteration process that people move toward righteousness.

Thus Confucius believed that only a “small man” would try to think without learning, or not reflect on what he has learned.

critical thinking

Well, Kyle, thank you for your effort. If there's something I object against our western culture, is that we think by numbers, while our eastern counter-parts think by feelings. I'm a fan of Zen philosophy, or culture, or way of thinking - I find it "only" more natural than any statistical charting, and more immediate, too. It's no wonder that the quick-responding martial fightings were born, and dwell, in the Far-East, while we still stick to the slow boxing, or football / soccer - et similia. Unfortunately, I can't invest in funding non-reflection-based management systems, but - believe me - if I could, I would. Thank you, keep going. 

Demystifying Lean Six Sigma: A Continuous Improvement Framework

53% of Fortune 500 companies use Six Sigma and up to 82% of those in the top Fortune 100 embrace the business improvement methodology. Research says that Six Sigma has saved companies over $400 billion .  40 years later the Six Sigma methodology is as popular as ever, with new variants and adaptations, like the Lean Six Sigma, making it more versatile for other industries and types of organizations as well.

Lean Six Sigma, the rising star of continuous improvement, promises to enable incremental innovation through a systematic approach to improving processes, products, or services. Attracted by the enticing potential of Lean Six Sigma methodology to fuel innovation, individuals are drawn towards training and certification while organizations rush to hire experts or implement Lean Six Sigma projects.

One can only wonder: is this yet another gold rush? Should you get certified in Lean Six Sigma, should organizations train their employees, or should you even consider implementing the framework?

To help you better understand if Lean Six Sigma could bring any value to you, either as an individual or as an organization, we’ll try to demystify the secrets of LSS in this article by exploring its definition, practices, and tools.

As with many of our articles, we seek to provide a comprehensive understanding of the topic, while also bringing forward practical advice which you can take into your everyday work. That being said, we advise you take your time with this one, bookmark it and come back to it to get a full grasp of the subject or to get more clarity.  

Table of contents

From six sigma to lean six sigma, can lean six sigma help you innovate.

• The benefits
• The drawbacks

Is Lean Six Sigma for you?

Lean six sigma in practice.

Socrates’ quote, "the beginning of wisdom is the definition of terms” comes to mind each time we want to dive deep into a topic. It’s a good reminder that understanding and clarity start with accurately defining and explaining the key concepts of the topic.

Traditional Six Sigma:

Before the Lean Six Sigma, there was Six Sigma. Not to go too far down the math rabbit hole, but maybe it’s good to clarify that "sigma" (σ) represents the standard deviation of a set of data points or a probability distribution. Standard deviation tells you how much the individual data points differ from the mean (average) value in a given dataset.

In the context of Six Sigma, Six refers to the number of standard deviations between the mean and the nearest specification limit. The more sigma away from the mean the limit is, the less defects and variation are acceptable, indicating higher levels of quality and process performance. Theoretically speaking, a “Six Sigma” process should not produce more than 34 defects per million opportunities (DPMO).

Now, back to simpler things.

In the context of manufacturing and quality control, Six Sigma uses statistical methods within the DMAIC (Define, Measure, Analyze, Improve, Control) framework. The objective of this systematic approach is to analyze process variability with the goal of minimizing deviations and defects, ultimately enhancing overall quality.

The concept was popularized and developed by Motorola in the 1980s and later adopted by other companies like General Electric. Over time, Six Sigma has evolved into a comprehensive business methodology, which takes us to the newer variant of Six Sigma, Lean Six Sigma.

Lean Six Sigma:

Lean Six Sigma is focused on simplifying processes and improving process reliability by bringing together the process improvement rigor and statistical analysis of Six Sigma with the waste elimination and efficiency focus of Lean.

Lean is rooted in the Toyota Production System and focuses on eliminating waste, increasing efficiency, and optimizing flow. It aims to create value by identifying and removing non-value-added activities or processes, resulting in streamlined operations and reduced lead times.

While both methodologies come from the manufacturing industry, LSS is mostly used in other functions across all industries. And while the Lean Six Sigma is typically closer to Lean, it’s important to have a good understanding of the Six Sigma philosophy as well.  

Lean Six Sigma brings together two sets of philosophies and tools. Balancing these elements can vary across projects. For instance, Lean's broader scope might lead to prioritizing its principles in some cases. On the other hand, Six Sigma's data analysis tools dig deeper into root causes of problems. To solve problems effectively, you need to blend these two approaches in a balanced way.

Can Lean Six Sigma really spark innovation? Is it just a tool for optimizing processes and increasing efficiency or can it unravel new opportunities? If you look at innovation strictly from the point of view of disruptive and radical services, products or markets, then you might want to look the other way because this is unlikely to take you there.

However, if you want a pragmatic and flexible approach to staying competitive and adapting to a changing environment, Lean Six Sigma can certainly support and drive incremental innovation .

At its core, Lean Six Sigma is guided by several principles, which depending on whom you ask, can be either three, five or ten. We chose the six most relevant ones.

• Customer Focus: LSS centers around understanding and meeting customer needs and expectations. It sees the customer’s perspective as critical for improvement, to helps align internal processes with external requirements in order to create value.
• Continuous Improvement (Kaizen): LSS promotes a culture of continuous improvement where incremental changes are consistently made to enhance processes, products, and services.
• Data-Driven Decision-Making : Data and facts guide decision-making in LSS. Statistical analysis and measurement systems ensure informed and effective problem-solving. These integrates with the Lean approach to identify and eliminate various forms of waste including defects, overproduction, excess inventory etc.
• Structured Problem-Solving: The DMAIC (Define, Measure, Analyze, Improve, Control) framework in Six Sigma provides a structured approach for problem-solving and process improvement.
• Standardization : LSS seeks to establish standardized processes and practices to ensure consistent and reliable outcomes.
• Leadership Commitment: Successful LSS implementation requires commitment from leadership to provide resources, support, and remove obstacles.

While Lean Six Sigma doesn't focus on radical shifts, it harnesses the impact of deliberate, incremental progress towards excellence. But before deciding on this approach, you should also be aware of the benefits and constraints.

• Revenue Growth: 
• Operating Margin: 
• Asset Efficiency:
• Rigidity and Complexity:

One drawback of LSS is its potential rigidity. The strict adherence to predefined methodologies and metrics might not be suitable for every situation. Teams might find it challenging to adapt the methodology to unique contexts or when dealing with complex, non-standard processes.

• Incremental Improvements vs. Breakthrough Innovation

LSS’s focus on incremental improvements might limit its suitability for fostering radical or disruptive innovation. While LSS excels at optimizing existing processes, it might not encourage the breakthrough thinking needed for transformative changes or entirely new products/services.

• Time Intensive:

LSS projects typically follow the DMAIC (Define, Measure, Analyze, Improve, Control) model, which involves a structured approach. While this ensures thorough problem-solving, it can also make projects time intensive. This could be a limitation in rapidly changing or dynamic environments where quick response and implementation are crucial.

Having clarified the basics of Lean Six Sigma, what it means and where it comes from, let’s now have a look at how it works in practice, and when it can be most useful. 

Maybe the most popular thing about Six Sigma, and consequently, Lean Six Sigma is the “belts” system which attests to the different levels of expertise and roles of practitioners. While not mandatory, the system provides a structured approach to learning and applying Lean Six Sigma methodologies, ensuring a standardized skill set across the organization.

These are the main belts, their meanings, roles, and how they contribute to the Lean Six Sigma framework.

From an organizational standpoint, it’s essential to remember that while these trainings and certifications can be very useful, in practice they aren’t worth anything unless you also provide the right conditions for Lean Six Sigma to thrive.

While these trainings and certifications can be very useful, in practice they aren’t worth anything unless you also provide the right conditions for Lean Six Sigma to thrive.

Some companies still hold on to the “secrets” of Lean Six Sigma for dear life, but the real secret is that you have to put in the work and explore how the tools can be leveraged to bring real value.  By applying the methods to practice, from on-the-job experience, testing, mentorship, the use of these tools, and learning from mistakes, you gradually start to connect the dots and drive real results.

Since our mission is to democratize innovation, providing free access to knowledge is one way to achieve that.

So, we created this Lean Six Sigma toolkit which you can download for free here .

It comes with a wide range of tools and techniques that are used throughout the DMAIC phases of the Lean Six Sigma framework. Which tools you use, and how, depends on the specific project, goals, and challenges at hand.

To conclude, a certificate under your belt (yes, pun intended), will not turn you into an expert unless you commit to LSS principles, you adopt the new mindset and get the appropriate support from top management.

As you can see, Lean Six Sigma is not the magic bullet to continuous improvement. Rather than sticking to one method, it’s better to first understand or make those in your team understand the bigger goal: bring innovation into the game through incremental improvements . The means by which you do it, should be decided internally.

But before jumping onto the LSS bandwagon, look for answers to these questions to help you understand what continuous improvement approach you need for your specific situation. Here’s a simple way that can help you figure out the methodology to choose. 

The core structure that is used in Six Sigma, as well as in Lean Six Sigma is the DMAIC model, which stands for the five steps: Define, Measure, Analyze, Improve, and Control . This roadmap helps you go after problems in a systematic manner, and it’s what makes the Lean Six Sigma successful.

Quite often people jump to improve things based on spontaneous ideas, but it’s important not to skip any step in the process. Employees might suggest improvement ideas on a regular basis, but unless you have some data and facts to support the hypothesis, you don’t know if they are feasible, or you won’t get management support to implement it.

You don’t want to dismiss their ideas either, nor make the whole process heavy and difficult for them. That’s why it’s good to have an idea management process in place. Among other things, it helps you hold on to the ideas you receive and get back to them once you have the data to back up the assumptions. It also does a lot of heavy lifting related to automating as much of the process as you can.

At the same time, to successfully implement and sustain LSS projects you need a variety of skillsets that come from other areas and not just from LSS training. This can be change management expertise, project management, effective communication and so on. 

So, let’s get down in the trenches to see how to put Lean Six Sigma in practice, what tools, knowledge and skills are needed for each step in the DMAIC model.

You will notice that there are a lot of tools and controls out there, and based on your context, you need to pick which ones are relevant. If you try to implement all of them, you’ll get nothing done and burn people out.

So, look for the lightest process of the following that covers each of these fundamental needs for your specific situation.

As the customer is at the center of any Lean Six Sigma improvement project, you need to identify the critical characteristics or parameters of a product or process that directly impact customer satisfaction or meet their requirements.

This is the CTQ , Critical to Qualit y concept, which is very important because any variation can result in a significant impact on the quality of the product or service from the customer's perspective. By identifying and measuring CTQs, you can focus the improvement efforts on the factors that matter most to customers.

By identifying and measuring CTQs, you can focus the improvement efforts on the factors that matter most to customers.

By the end of the Define stage, you should have a clear understanding of the problem, the goals of the project, and the scope of work. This stage sets the foundation for the rest of the DMAIC process, guiding subsequent efforts in data collection, analysis, improvement, and control.  

In a nutshell for the Define stage you want to have the:

• Knowledge : Understanding of project scope, goals, and objectives. Knowledge of the process under study and its relationship to business outcomes.
• Skills : Problem definition, stakeholder management, project scoping.
• Tools : Project Charter, SIPOC (Suppliers, Inputs, Process, Outputs, Customers) diagram, Process Mapping, 5S, Voice of the Customer (VOC) analysis, JTBD

You can discover these tools in the free Lean Six Sigma toolkit which explains in more detail what they are and how to use them. When it comes to the VoC analysis, while it’s a standard tool when working with the LSS framework, there are some nuances we’d like to bring up.  VoC has lost a bit of its popularity and as some research showed, there is a disconnect between the business value of VoC programs and customer experience.

Basically, they say that VoC programs usually underdeliver. It doesn’t mean it can’t still be a valuable tool, but like every other tool out there, it depends how you use it and put it into practice. An alternative, even though not a part of the usual Lean Six Sigma toolkit, is the Jobs To Be Done framework. The difference between the two lies in how they approach the goal of better understanding customer needs to create or improve products and services. Through VoC you collect feedback, ideas and suggestions from customers through surveys, interviews, forms, social listening etc.  All of that can be valuable, but instead of solely analyzing customer feedback, JTBD seeks to uncover the fundamental problems or tasks that customers are looking to solve, which they typically aren’t great at communicating themselves. The emphasis is on understanding the context in which customers make purchasing decisions and how a product or service fits into their lives to fulfil specific needs. You can read all about JTBD here and get the free toolkit for JTBD here.

Before making any improvements, you ought to collect data to figure out where you are right now. By comparing the data before and after the improvement, you can see if they actually work.

In this stage, the focus shifts from defining the problem to quantitatively measuring the current state of the process. The main objectives of the Measure stage include:

• Data Collection Plan: Design a plan to gather necessary data.
• Data Collection : Execute the data collection plan.
• Measurement System Analysis (MSA) : Ensure reliable measurement methods.
• Process Mapping : Visualize process steps and interactions.
• Baseline Performance Metrics : Calculate current process metrics.
• Process Capability Analysis : Evaluate process's ability to meet requirements.
• Data Analysis: Apply statistical methods to identify patterns.
• Current State Assessment: Assess process performance against goals.
• Establishing Baselines: Set benchmarks for performance metrics.

In a nutshell for the Measure stage you will need:

• Knowledge : Data collection methods, basic descriptive statistics.
• Skills : Data gathering, process mapping, understanding measurement systems.
• Tools : Data Collection Plan, Process Map, Histogram, Pareto Chart.

Analyze, the third stage of the DMAIC model can be considered one of the more challenging stages due to its complexity and the critical decision-making involved.

In this stage, the focus is on analyzing the data collected in the previous stages to identify the root causes of problems and to gain insights into the process. The main objectives of the Analyze stage include:

• Data Validation: Ensure accurate and reliable data.
• Data Visualization : Create visuals to identify patterns.
• Root Cause Analysis : Identify underlying causes systematically.
• Statistical Analysis: Quantify relationships between variables.
• Hypothesis Testing: Test assumptions using statistics.
• Process Mapping : Refine process maps based on analysis.
• Data Segmentation : Break down data for insights.
• Identify Improvement Areas: Spot inefficiencies and defects.
• Confirm Root Causes : Validate hypotheses through analysis.
• Risk Assessment: Evaluate potential solution risks.
• Recommendation Development : Create improvement suggestions.

Lean Six Sigma practitioners need to be equipped with strong analytical skills, a deep understanding of statistical methods, and the ability to navigate complex processes to succeed in this phase.

• Knowledge : Statistical analysis techniques, root cause analysis methods. 
• Skills : Identifying patterns, analyzing data, finding root causes.
• Tools : Both Quantitative (Pareto, Histogram, Run charts, Regression Analysis, etc.) and Qualitative tools (5 Whys, FMEA, Fishbone diagram – identify causes of a problem (establish and clarify the cause-effect relationship) XY (cause effect) matrix – prioritize potential causes identified with Fishbone), Scatter diagram (to suggest the strength of a relationship between two variable).

There are many tools you can use in this phase, and which we described in more detail in the toolkit . You don’t have to use them all and no single tool can fix all problems. 

In essence, the Improve stage aims to develop, test, and implement solutions to address identified root causes and improve the process's performance. The Improve stage embodies the spirit of continuous improvement , a core Lean principle.

Solutions are tested, refined, and adjusted iteratively to achieve the best possible outcome.

The Improve stage in Lean Six Sigma's DMAIC process involves:

• Solution Generation : Develop potential solutions.
• Solution Evaluation : Assess and prioritize solutions.
• Pilot Testing : Test solutions on a small scale.
• Data Collection : Gather data on solution effectiveness.
• Refinement : Adjust solutions based on data.
• Implementing Changes : Deploy refined solutions.
• Monitoring Results : Track solution impact.
• Standardization : Establish new process standards.
• Documentation : Document changes and outcomes.

In short, for this stage you need:

• Knowledge : Creativity techniques, process redesign concepts.
• Skills : Generating solutions, piloting changes, evaluating alternatives.
• Tools : Brainstorming, Design of Experiments (DOE), Simulation, How might we statements, ideation workshop, idea challenges, Lean instruments: Kanban , Kaizen, 5S, Standardized work – SOP (template good for toolkit), FMEA.

Maybe one of the most important, and sometimes overlooked steps in the DMAIC model is the Control one. This is what helps you ensure that all efforts have not been in vain, and that you can sustain and guarantee long term performance . 

A lot of people stop when they see results and just move on, excited to start something new. The assumption is that if things have worked, the process controls are also in place.

So, before you close up your improvement project you want to make sure you have a system or process that monitors the results over time. You should collect data on a regular basis, whether that is daily, weekly, or monthly to make sure that things stay where they are, in that new Improve state.

Before you close up your improvement project you want to make sure you have a system or process that monitors the results over time

This is especially important for new employees that were not involved in the improvement process. When new people come on board you want to make sure the new behaviors and changes don’t fall apart. On most projects, the goal is to have 12 months or more of sustained improvement.

For example, you can use visual aids that make it easier to understand how to do certain jobs. It will make it easier for new people and will reinforce the behaviors. Also, keep in mind the incentives needed to make sure that improvements are encouraged and supported.

For a higher rate of success in the control phase, you’ll need:

• Knowledge : Process control concepts, mistake-proofing methods.
• Skills : Implementing and sustaining improvements, developing control plans.
• Tools : Control Plan, Statistical Process Control (SPC) charts, Standard Operating Procedures (SOPs)

Lean Six Sigma plays a pivotal role in continuous improvement, yet the tools and framework are not the only part of the equation. While mastering these concepts is essential, to make LSS effective, you need to tailor it to your own challenges. This, however, is no easy feat.

The truth is, the toolbox of Lean Six Sigma, while powerful, isn't always the best fit for every scenario. Sometimes, the most efficient path forward involves embracing simpler tools that match the complexity of the task at hand. With a strategic approach you can avoid unnecessary complexity, and ultimately achieves the desired outcomes of continuous improvement and ultimately, incremental innovation.

At the same time, while certifications certainly hold value, it's essential to recognize that their primary contribution should extend beyond individual achievement. Indeed, fostering knowledge transfer can translate to improved bottom-line results.

Yet, at the core, the ultimate objective remains elevating organizational performance. The path to success in continuous improvement is paved with practical experience, continuous learning, and the application of knowledge. This can very well be achieved with frameworks like Lean Six Sigma, or with something much simpler. The key is figuring out what best fits your needs, and then just getting started.

If you are ready to embark on this continuous improvement journey, we want to arm you with plenty of practical resources on the topic. And, in case you need one, we also provide the platform with practical, tailored templates where you can start your Lean Six Sigma project, or other continuous improvement programs, within minutes, and for free. 

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What Is Lean Six Sigma? A Comprehensive Guide to Understanding the Methodology

• Written by Contributing Writer
• Updated on June 16, 2023

In today’s rapidly changing and competitive business landscape, finding ways to continually enhance efficiency, optimize processes, and deliver exceptional quality is critically important. Lean Six Sigma is a powerful methodology that drives transformative improvements and delivers measurable results. But what is Lean Six Sigma exactly, and what is the Six Sigma methodology?

Keep reading to learn the answers to “What is 6 Sigma?”, “ What is Lean Six Sigma certification? ” and more.

What Is Lean Six Sigma? The Origins of Lean Six Sigma

To fully understand the essence of Lean Six Sigma, it is essential to explore its origins and the combination of two influential methodologies: Lean and Six Sigma.

The roots of Lean can be traced back to the Toyota Production System (TPS) developed by Toyota in the 1950s. Toyota aimed to eliminate waste, improve efficiency, and maximize value for customers by implementing a set of principles and practices that prioritized continuous flow, just-in-time production, and respect for people. The success of TPS led to the widespread adoption of Lean principles across industries worldwide.

Six Sigma emerged at Motorola in the 1980s as a statistical approach to quality management. Driven by the goal of minimizing defects and reducing process variation, Six Sigma utilizes data analysis, problem-solving methodologies, and rigorous measurement techniques to identify and eliminate root causes of errors. Over time, Six Sigma gained recognition as a systematic and data-driven approach to improving processes and enhancing product quality.

Recognizing the synergies between Lean and Six Sigma, organizations began integrating the two methodologies, giving rise to Lean Six Sigma. By combining Lean’s waste reduction techniques and focus on value stream optimization with Six Sigma’s statistical analysis and problem-solving tools, Lean Six Sigma offered a comprehensive framework for process improvement and performance optimization.

What Is Meant By Black Belt and Green Belt?

Green Belt and Black Belt are two levels of expertise within the Six Sigma methodology.

What Is Six Sigma Green Belt?

Green Belts are trained individuals who support improvement projects and work under the guidance of Black Belts. They understand the DMAIC methodology well and use statistical tools to analyze data, identify process issues, and improve performance.

What Is Six Sigma Black Belt?

A Black Belt is an advanced practitioner who leads and manages Six Sigma projects. Black Belts have in-depth knowledge of the DMAIC methodology, statistical analysis, and process improvement tools. They drive significant improvements, reduce defects, and work closely with management to align initiatives with organizational goals.

What is Lean Six Sigma, and What are Its Core Principles?

Lean Six Sigma operates on a set of fundamental principles that guide its methodology and approach to process improvement, including:

Define, Measure, Analyze, Improve, Control (DMAIC) Methodology

At the core of Lean Six Sigma lies the DMAIC methodology. So, what is DMAIC, anyway? Let’s dig in.

• Define: Clearly define the problem or opportunity for improvement and establish project goals.
• Measure: Identify and measure the critical aspects of the process to establish a baseline and understand the current performance.
• Analyze: Analyze the data collected to identify root causes, bottlenecks, and areas of improvement.
• Improve: Develop and implement solutions to address the identified issues and optimize the process.
• Control: Establish control measures to sustain the improvements and monitor the process to prevent regressions.

The Five Lean Six Sigma Principles

Lean Six Sigma embraces five core principles that serve as guiding pillars for process improvement:

• Customer Focus: Prioritize understanding and meeting customers’ needs to deliver value-added products and services.
• Process Focus: Identify and map the end-to-end processes, seeking to eliminate waste, streamline flow, and improve overall efficiency.
• Data and Fact-Driven Approach: Base decisions on reliable data and facts, using statistical tools and analysis to drive problem-solving and improvement efforts.
• Teamwork and Collaboration: Foster a culture of collaboration, empowering cross-functional teams to work together and share knowledge to achieve common goals.
• Continuous Improvement: Promote a mindset of continuous improvement, encouraging ongoing efforts to identify and implement enhancements in processes, products, and services.

Data-Driven Decision Making

Data-driven decision-making is a cornerstone of Lean Six Sigma. It emphasizes using data and statistical analysis to gain insights, identify trends, and make informed decisions. By collecting and analyzing relevant data, organizations can objectively assess the current state of processes, pinpoint areas of improvement, and measure the impact of implemented changes.

What Are the Benefits of Lean Six Sigma?

Now that you’ve understood the answer to “What is Lean Six Sigma?”, it’s time to review the benefits. Some of the most significant benefits of Lean Six Sigma include:

• Improved quality and customer satisfaction: By consistently delivering products and services of higher quality, organizations can enhance customer satisfaction, build a strong reputation, foster customer loyalty, and gain a competitive edge.
• Increased efficiency and productivity: Streamlined operations can help organizations meet customer demands more effectively, enhance capacity utilization, and achieve higher output levels without compromising quality.
• Reduced costs and waste: Lean Six Sigma targets waste reduction, such as overproduction, excess inventory, unnecessary motion, and defects. By identifying and eliminating waste, organizations can reduce costs associated with rework, scrap, excess inventory holding, and unnecessary resource consumption.
• Improved employee engagement and morale: Lean Six Sigma promotes employee involvement, empowerment, and recognition. Organizations foster a culture of continuous improvement and engagement by involving employees in problem-solving activities, providing training, and acknowledging their contributions. This boosts employee morale, job satisfaction, and a sense of ownership.

How Lean Six Sigma Is Used in Various Industries

Lean Six Sigma has proven to be a versatile methodology that can be applied across various industries. Here’s a breakdown of how Lean Six Sigma is used in different sectors:

Manufacturing

Lean Six Sigma is widely utilized in manufacturing industries (in fact it started here!) to optimize production processes, reduce waste, and enhance quality control. It helps organizations streamline supply chains, improve inventory management, and eliminate bottlenecks. By implementing Lean Six Sigma principles, manufacturing can achieve greater operational efficiency, higher product quality, and improved customer satisfaction.

Lean Six Sigma is crucial in enhancing patient care, reducing medical errors, and improving operational efficiency in the healthcare industry. It helps hospitals and healthcare facilities streamline administrative processes, reduce waiting times, and improve patient flow. Lean Six Sigma is also utilized in healthcare quality improvement initiatives, such as reducing medication errors, improving surgical outcomes, and enhancing patient safety.

Service Industries

Lean Six Sigma principles apply to service industries, including banking, insurance, hospitality, and telecommunications. These sectors often have complex processes and customer interactions. Lean Six Sigma helps organizations identify and eliminate inefficiencies, reduce customer wait times, streamline service delivery, and enhance customer satisfaction. It also supports service quality improvements, such as error reduction, faster response times, and enhanced service consistency.

Government and Non-Profit Organizations

Lean Six Sigma is increasingly being adopted by government agencies and non-profit organizations to improve process efficiency, enhance service delivery, and achieve better outcomes. These sectors face unique challenges in public services, compliance, and resource constraints. By implementing Lean Six Sigma, government agencies, and non-profit organizations can streamline administrative processes, reduce waste in resource allocation, improve decision-making, and enhance the effectiveness of their programs and services.

Wrapping Up

In conclusion, Lean Six Sigma is a powerful methodology that combines Lean principles with Six Sigma’s data-driven approach to achieve operational excellence. What is Lean Six Sigma? It is a comprehensive framework that empowers organizations to streamline processes, eliminate waste, and drive continuous improvement.

Ready to master Lean Six Sigma and unlock its transformative potential in your organization? Check out this online Lean Six Sigma certification training to gain the knowledge and skills to drive impactful process improvements and kickstart your quality management career.

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What are the Lean Six Sigma Principles?

21 June, 2021

But it may not be a new methodology that yields the best solution. As companies fine-tune their processes for optimal efficiency and work to maintain superior standards of quality, a combination of the tried and true Lean method and Six Sigma approach might just be the ticket for success.

Concepts of Lean Six Sigma

The primary aim of the Lean method is to reduce waste. The goal of Six Sigma is to reduce variation for optimal quality control. The discipline known as Lean Six Sigma (LSS) blends these two approaches. Refinements to the production process are essential to managing and reducing the 8 wastes analyzed by the Lean method. By paying careful attention to how waste affects production processes (and vice versa), business leaders can take significant strides toward optimizing their operations.

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5 Lean Six Sigma Principles

Experts recommend that you keep these 5 key Lean leadership principles in mind to help ensure the success of your LSS project.

Work for the customer

The primary goal of any change you want to implement should be to deliver maximum benefit to the customer. Establish a clear standard of quality early on that’s defined by what the customer or market demands.

Find your problem and focus on it

During the re-tooling processes, it’s easy to get caught up in a whirlwind of desired changes and lose focus on the initial problem. Gather data that shows you where your specific problem area lies and concentrate on refining only that area of your business. Any attempt to broadly alter the company or change the product will likely derail the LSS process.

Remove variation and bottlenecks

Once you’ve identified the problem, it’s time to look for ways to decrease opportunities for defects. These openings often come in the form of long, intricate processes that leave significant room for mistakes and waste. Streamlining or removing these functions is an excellent way to achieve quality control and efficiency.

Communicate clearly and train team members

Lean Six Sigma fundamentals require that all team members are versed in LSS, know the goals of the project, and are informed of its progress. Six Sigma methodology can cause tremendous change and requires specialized focus on the part of management. Advanced certifications in Six Sigma are critically important for reducing the risk of project failure and ensuring that the entire process run smoothly.

Be flexible and responsive

Change and Lean Six Sigma go hand-in-hand. A process or function that is identified as faulty or inefficient, must be refined or removed. Clinging to a failing approach is not an option with LSS. Change and change management can be challenging and painful, but it’s a small price to pay for what every business leader strives for: a leaner, stronger, more competitive company.

About Purdue’s Online Lean Six Sigma (LSS) Certificate Program

Purdue University offers comprehensive online Lean Six Sigma (LSS) certificate programs designed for working professionals with varying levels of Lean Six Sigma experience. The online Lean Six Sigma certificate courses prepare professionals to satisfy the immense demand for Lean expertise, skills and certification.

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Lean Six Sigma is a process improvement methodology designed to eliminate problems, remove waste and inefficiency, and improve working conditions to provide a better response to customers’ needs.

It combines the tools, methods and principles of Lean and Six Sigma into one popular and powerful methodology for improving your organization’s operations.

Lean Six Sigma’s team-oriented approach has proven results in maximizing efficiency and dramatically improving profitability for businesses around the world.

Still wondering, “What is Lean Six Sigma exactly?” Read on for an in-depth dive into what it is, why it matters, and how to do it right.

There are three key elements to Lean Six Sigma.

Tools and techniques : A comprehensive set of tools and analytical techniques that are used to identify and solve problems.

Process and methodology : A series of phases that organize the use of the problem-solving tools to ensure that the true root causes are found and that a solution is fully implemented.

Mindset and culture : A way of thinking that relies on data and processes to achieve operational performance goals and continuously improve.

These three elements reinforce each other. Analytical techniques are not used effectively unless there is a process for applying them and a mindset of continuous improvement creating the need for them. An improvement process does not produce the desired results unless it includes the tools and techniques that define the activity of the process steps and there is a culture that insists on systemic data-based approach to solving problems.

Finally, a culture that seeks to continuously improve will be frustrated if there are no tools and techniques for analysis and no process or methodology that can be applied to organize and focus the improvement efforts. Fortunately, the Lean Six Sigma approach to business improvement includes all three layers.

Let’s take a look at the history of Lean Six Sigma, and how the different parts of this methodology were formed to become the process improvement approach we know today.

What is continuous improvement?

Continuous improvement as a business strategy and discipline developed as an offshoot of Frederick Winslow Taylor’s Principles of Scientific Management . Taylor described business as a series of interlocking workflows or processes that should be managed using data.

In the 1930’s Walter Shewhart developed a set of management disciplines for process control and continuous improvement. These disciplines were based upon Taylor’s principles of business workflows and a reliance on data. Shewhart’s work is the foundation for the engineering and management disciplines of Quality Assurance and Quality Control found in most organizations today.

One of Shewhart’s students and proteges was Edward Deming, who used these principles to remake the Japanese automotive industry into a global quality and engineering powerhouse following World War II.

Lean was developed in Toyota as part of the Toyota Production System , which was built around the work of Shewhart and Deming. Toyota had been a client of Deming and established its operational management practices on the principles he taught. The fundamental driver of Lean is the elimination of waste. In fact, a good description of the Lean approach is, "a set of tools that assist in the identification and the steady elimination of waste."

If a company is doing large scale, high-quantity production like Toyota; then a process with waste in it means that company is creating large-scale, high quantity waste. No company wants to do this. The Lean approach uses tools to analyze the business process.

Five principles of lean manufacturing

• Value Value is determined by what the customer considers to be important within a product or service, rather than what the individuals developing or delivering the product or service consider important.
• Value Stream The set of business activities and steps involved in creating and delivering products and services to the customer; it is the connection of the steps together rather than considering each step in isolation.
• Flow The degree to which there is smooth uninterrupted flow of activities that add value to the customer, rather than waste and inefficiency that impedes the flow through the value stream.
• Pull The degree to which the value stream is only processing products and services for which there is a customer demand, rather than creating something and hoping someone wants it.
• Perfection The continuous assessment of value stream performance to identify and improve the value created and delivered to the customer, rather than resisting changes that improve the process of creating and delivering customer value.

Three types of waste

Using the terms of the Toyota Production System, the Lean methodology identifies and strives to eliminate three types of waste:

• Muda Non-value added work – pure waste.
• Mura Unevenness in flow – unpredictable variation requires compensation elsewhere in the system.
• Muri Over-burdening resources beyond their normal rated capability – stresses and damages resources so that they are unable to do a normal workload.

As you can probably tell from both of these lists, the principles of Lean can be applied to any business process or operation, not just manufacturing. It is now used in literally all functions and all industries.

Six Sigma was first developed at Motorola during the late 1980s. The methodology was pioneered by Bill Smith, a quality engineer, whose goal was to improve the way the quality and measurement systems worked so as to eliminate errors. The Motorola systems tolerated error rates that created too much scrap, rework, redundant testing and often customer dissatisfaction.

The Six Sigma approach focused on identifying and eliminating anything that caused variation in the process. When the variation is gone, the process results can be precisely predicted – every time. By designing the system so that these precisely predictable results fall within the zone of acceptable performance from a customer perspective, process errors are eliminated.

But the engineers at Motorola went one step further. They knew from experience that many process changes were not effective because they did not get to the root cause of the problem. Also, the changes they made would not stick, as the operators reverted back to doing things in the original manner over time. Six Sigma was organized with five phases to address these issues.

What are the five phases of Six Sigma?

• Define In this phase the boundaries for the process being analyzed are set and the expectations or desired performance for that process are defined from a customer perspective. This is to ensure a change does not degrade the customer experience, but instead enhances it.
• Measure In this phase the current performance of the process, product or service is measured to determine what is actually occurring, especially from a customer perspective. This is to ensure the analysis and solution are based on actual performance, not theoretical or anecdotal information.
• Analyze In this phase the process, product or service is analyzed using the measured data to determine the source or sources of the variation that are causing the problem. This is to ensure the true root cause(s) is identified and not just a symptom.
• Improve In this phase the possible changes to the process, product or service are assessed and a solution set of changes is designed and tested. This is to ensure the solution creates the desired effect and that the variation is reduced or eliminated.
• Control In this phase the changes are implemented, the supporting systems are also updated and the process, product, or service is put under control – normally statistical process control – to ensure the solution is fully implemented in a sustainable manner and to identify if performance starts to degrade.

The methodology of Six Sigma will work with any process, product or service that has a definable performance goal and measurable characteristics, because the methodology heavily relies on data.

Lean and Six Sigma have been combined because, although they are different, they are complementary. The similarities allow them to mesh together well. The differences ensure that there are analytical tools and solution options available that will improve the process, product or service. It is due to the similarities that both types of analysis can be done simultaneously on the same process, product, or service.

Similarities of Lean and Six Sigma

• Both rely on a definition of value that is based upon the customer experience. The customer is king (or queen).
• Both use a process flow mapping approach to understand the process. Even when the analysis is based upon a product or service, there is a process that is associated with creating and delivering that product or service.
• Both rely on data for determining current performance and for determining the impact of future performance. The data collected in a Lean Six Sigma project can often be used to support both Lean analysis and Six Sigma analysis. The reliance on data helps to ensure that the true root cause is identified.
• Both are applied using improvement projects that typically will be implemented by a small cross-functional team. The duration of the project and the size of the team will depend upon the scope and scale of the process, product or service being analyzed for improvement.
• Both have migrated beyond the manufacturing operation and are now used for all functions and for all internally facing and externally facing processes. They are also used in all industries including industrial, consumer, government, education, and non-profits.
• Improvements based upon using either approach will normally both reduce waste and reduce variation. Removing wasted steps and activities (muda) eliminates sources of variation, and removing variation eliminates wasted process capacity and steps associated with accommodating the variation (mura and muri).

However, there are some differences in the two approaches. These differences do not create a conflict, rather they provide multiple paths that can be used to reach a similar destination. A Lean Six Sigma project should let the nature of the defect, as defined by the customer value, and the current state of the process, product, or service dictate which sets of tools are most appropriate. The final solution is often a hybrid combination of both Lean improvements and Six Sigma improvements.

What is the difference between Lean and Six Sigma?

• Different focus for problem identification – Lean is focused on waste (muda, mura, muri) and Six Sigma is focused on variation, any deviation from the target performance.
• Different types of techniques – Lean primarily uses visual techniques for both analysis and solution creation that are supported with data analysis. Six Sigma primarily uses statistical techniques for analysis and solution creation that are supported with data visualization. This leads to a myth that Lean is easier than Six Sigma, because the visual analysis of Lean is easy to understand, while many people are intimidated by Six Sigma’s numerical analysis. The reality is that both types of analysis are easy to perform with today’s statistical support tools.
• Different types of documentation for the solution – the Lean solution is documented with a revised value stream map that leads to changes in workflows and often changes in work instructions at many of the steps in the process. The Six Sigma solution is documented with changes in setup procedures and the control plan for monitoring the process and responding to variation. It will also impact work instructions and frequently leads to changes in the measurement approach or systems.

The two approaches are compatible in so many ways that it was easy to merge them into one methodology so as to get the synergistic effect of combining them. Lean Six Sigma, as it is normally practiced, avoids most of the pitfalls from earlier failed approaches.

Lean Six Sigma principles

Let’s outline the principles that have helped to make Lean Six Sigma so effective. I have been directly involved in the successful implementation of Lean Six Sigma in many organizations, and I have done consulting in several organizations who had tried and failed to implement an effective Lean Six Sigma program. In the successful programs, the following principles were adopted. In the failed implementations, at least one or more principle was not followed.

Addressing a real-world problem

Lean Six Sigma is both a top-down and bottom-up methodology. The top-down element is associated with problem selection. The Lean Six Sigma project teams are focused on real-world problems that are impacting customers and processes right now. Often the team members are feeling the effect of the problem with rework and repair activities or addressing customer complaints. This lends a sense of urgency and importance to the project. It is not just "busy work," it is real work.

One of the reasons for the failure of the Quality Circle programs of the 1980s was that every team could choose its own project. While this sounds great for empowerment, often the projects selected were not real-world problems. In one organization I worked with, one of the first projects selected by a team was to repaint the lunch room and put up new curtains. Soon the whole initiative was viewed in the organization as a "fun" party time activity, but not related to real business improvement.

It is often hard to get the organization to recognize the importance of this methodology for business success. Buy-in is much easier to achieve when both management and the team understand the importance of identifying and fixing the problem. But management does not dictate a problem and solution. Rather the analysis by the team determines the true root cause.

Analysis is accomplished by a team

A Lean Six Sigma project is normally staffed by a cross-functional team that is involved with different aspects of the process being analyzed. Many business processes are cross-functional and a cross-functional analysis is needed to prevent sub-optimization of the process. Improving one step at the expense of another step does not eliminate waste or variation, it just moves it to a different step in the process.

A problem I have seen in several Lean Six Sigma implementations was that the Green Belt and Black Belt project leaders worked on their own to find and fix the problem without the help of a cross-functional team. If the process and problem were small and the project leader understood the process, this would prove effective. However, with large cross-functional processes and projects, or in some cases when the project leader had no background in the type of process or problem being analyzed, the projects would become stalled and delayed.

By including a cross-functional team, all the perspectives of the organizations that are involved and impacted by the project are included in the problem analysis, and even more importantly in the development of the solution. The in-depth knowledge of the different team members is helpful for understanding the problem and the implications of the data. These different perspectives are crucial to help the team create a solution that addresses the immediate problem and often will help to eliminate waste and variation in other aspects of the process.

Analysis is focused on a process

Lean Six Sigma is best used for analyzing processes. Even when the problem under investigation is an obvious product problem, Lean Six Sigma will be much more effective when it is applied to the process that designs or builds the product, rather than looking at just the product itself. That is because the analysis is meant to investigate and improve actions, and actions are the steps of processes. Actions seldom happen in a vacuum with no impact from preceding or succeeding actions. Instead they must be considered in the context of the process in which they are occurring. The Lean value stream map or Six Sigma process map provide a picture of that process.

On numerous occasions, I have found that the creation of a map of the process immediately led to an understanding of what was happening, and recognition of some of the underlying problems that are hidden when an individual is only aware of their step in the process. On a few occasions I have encountered a project team that focused solely on a product defect without considering the process that created or used the product. While they could identify the defect, they could not determine the actual cause and create a solution until a process map was created.

Analysis is based upon data

Lean Six Sigma relies on data, not guesses. The Lean value stream map is verified with a walk-through of the process, and then data is collected at each step. The current condition of the process, product or service is measured in the Measure phase. This includes measuring the problem or defect and measuring anything that is done correctly. The data that is captured is used for analysis to determine the actual state of what is happening, not an assumed state. This analysis verifies the underlying causes so that the correct problem is fixed. But the reliance on data does not stop there. When a solution has been created, data is collected to determine if the solution has truly fixed the problem. And then data is used to ensure the solution stays in place and the problem does not return.

One of the challenges that continuous improvement and problem-solving initiatives have had over the years is a difficulty accepting the reality of the current conditions. Businesses are often in denial about problems and issues. I recently worked with a company that was implementing Lean Six Sigma. One of the initial project teams was tasked with resolving a product issue that created large levels of rework in their operation and was the source of numerous customer complaints. The problem had been "solved" on numerous occasions by putting tighter controls on the process step that "caused" the problem. Except when we actually measured what was happening in each step, we found the problem was really due to several other factors. Because of "politics" and paradigms, the management at first rejected the analysis. But when presented with the data, they eventually recognized where the problems were originating and an effective solution was implemented. It was the data that finally broke through the paradigms about the problem.

Understand the impact of the process sigma

This next principle is focused on the Six Sigma analysis. The practical impact of sigma is that it represents the amount of normal variation that occurs. It is always tied to a specific parameter or characteristic that is being measured. Same attributes of a product or process will have virtually no variation. That attribute never changes, no matter how often the product or process occurs. Other attributes do have variation. There is an average value, but there is uncertainty about any specific instance. Sigma is the statistical measurement of that uncertainty.

• One sigma represents the boundaries for a little over two thirds of the occurrences.
• Two sigma represents 95% of the occurrences.
• Three sigma represents over 99% of the occurrences.
• By the time you get out to six sigma, there are only about 3 chances in a million that normal variation could cause the attribute being measured to be that different from the average value.

Sigma represents variation, it says nothing about acceptability. Notice that I haven’t yet mentioned whether the attribute being measured is acceptable from a customer or standards viewpoint. An attribute could have a very small sigma, essentially no variation. But if the average value of that attribute is outside the bounds of what the customer finds acceptable, it just means that it is always defective. By the same token, an attribute could have a very large sigma, there is a high level of uncertainty. But if the customer has no expectations concerning that attribute, it will always be acceptable regardless of the variation.

The reason the Lean Six Sigma methodology is concerned about sigma is not for the purpose of customer acceptance. Rather when high variation and uncertainty exists within key attributes or parameters, it causes the expense of extra time and money, and it will often lead to the creation of defects. Remember, we are in a process and the outputs of one step become the inputs of another step. When the inputs have a great deal of uncertainty, which is indicated by a high sigma, the succeeding steps should be able to accommodate the full range of possibilities for the value of that attribute. That will often add cost and complexity. Lowering sigma can simplify and streamline the entire process.

Solution addresses the real root cause(s)

Lean Six Sigma is one of the most powerful problem-solving and continuous improvement methodologies because it identifies the characteristics of the real problem. Some methodologies start with the assumption that every problem has a unique or special cause, and if that cause can be identified and eliminated or controlled, the problem goes away. Other methodologies start with the assumption that the problem is a common occurrence within the process. The process is fundamentally flawed or inadequate and if the process were changed to avoid this flaw or correct this inadequacy, the problem goes away.

Both goals are admirable and in fact are actually quite similar. But the way to fix the first problem is to put in a place a "spot correction" to control the unique cause, and the fix for the second approach is to re-engineer the process. Unfortunately, selecting the wrong solution strategy does not improve the situation and can often make things worse. Lean Six Sigma employs the tools to differentiate between whether the problem is a special cause or a common cause. By making this differentiation, the project team can go on to find the true root cause or causes. Also, the team can create a solution strategy that will appropriately address the problem. If it is a special cause, they can implement a special solution. If it is a common cause, they can redesign the process.

Solution includes a control system to help it "stick"

Lean Six Sigma does not end with identifying the problem or even with implementing a solution. The final phase of Lean Six Sigma is the Control phase. There is a natural resistance to change in most organizations. For many people and systems, change is hard. Habits must be broken, new methods learned, new information is required. In the Lean Six Sigma Control phase, the solution is implemented and the organization begins to use it. While this is happening, the project team is ensuring all of the supporting systems are also updated to reflect any changes and they provide training and coaching for process operators and managers on the use of the solution. This even includes ensuring the control systems that monitor the process are in place to identify if the process begins to revert back to the previous behavior. The project team does not declare victory and disband just because they have successfully demonstrated their solution once. Rather they stick with it through a statistically significant number of occurrences. This both demonstrates the solution really solved the problem and that the operators and managers are equipped and able to manage the improved process.

I worked with a company in Chicago at one point to address a recurring problem in their purchasing department. The solution was a straightforward process change to eliminate a common cause problem. As I looked over the historical documents associated with this problem, I found that the previous solutions were similar to the one we had developed. They had been put it place and used for a year or two, and then slowly modified until the problem returned. The reason for the modifications was based upon how the senior management measured the effectiveness of the purchasing department. Rather than measuring the entire purchasing process, the measurements were tied to one step in the process. Optimizing that step led to sub-optimization in several other steps which created the problem. This time when a solution was implemented, I made sure the corporate measurement system was modified to measure the entire purchasing operation and not just one step. These are the types of issues often addressed in the Lean Six Sigma Control phase.

Benefits of Lean Six Sigma

Lean Six Sigma is a continuous improvement methodology. However, a legitimate question is, what does it improve? Does it increase sales or profits? Does it improve customer satisfaction and lower complaints? Does it lower costs, improve incoming quality, outgoing quality or the cost of quality? Does it improve employee morale? Does it increase your pay and benefits, or improve your promotability? Does it create world peace and solve world hunger? "Yes" to all of these – except the last two. Let’s look at benefits for the business and then benefits for the individuals who attain a level of certification in Lean Six Sigma.

Lean Six Sigma is a continuous improvement methodology for an organization. So, we would expect organizational benefits. In fact, the General Electric company has claimed to have realized over $2 billion of cost savings from Lean Six Sigma . Let’s consider the nature of the benefits and their implication.

Simple processes

Lean Six Sigma will simplify the business processes. The cross-functional value stream maps will identify areas of waste and inefficiency. Many of the processes have embedded rework and work-arounds for persistent problems. When the wasted effort is removed and the rework and workarounds are no longer needed, the remaining processes are simple and often much easier to manage and control. This results in a faster process, which leads to better customer service and higher customer satisfaction. Both of those will normally lead to greater sales. In addition, the simpler, faster process will lower overhead costs which will increase profits. Finally, simpler processes have fewer opportunities for errors. Therefore, they normally are characterized by higher quality and fewer defects.

Fewer errors and mistakes

Let’s dig deeper into that benefit of fewer errors and mistakes. Lean Six Sigma starts with a definition of acceptable quality based upon what the customers value. This external focus on quality prioritizes the continuous improvement efforts to address the problems that have the most impact on business success. In addition, the reliance on data to define problems rather than gut feel or anecdotes further prioritizes the improvement effort on the real problems in the organization. The result is that the improvements fix real problems and bring them to a level that is acceptable to the real customers. So, it is not just that Lean Six Sigma addresses errors and mistakes in the business, but rather that Lean Six Sigma addresses the errors and mistakes that matter the most.

Predictable performance

Simple processes are easier to control and manage than complex processes, especially those processes with fewer errors and mistakes. But added to these benefits, Lean Six Sigma has a focus on reducing variation within a process. With less variation, processes become more predictable. That means predictable cycle time, predictable quality output, and predictable costs. And these can lead to better customer service, fewer complaints, and higher profits. This predictability becomes a tremendous advantage for an organization when operating in an environment of fast moving changes. Changing technology and customer expectations are already creating an unstable business environment. Without predictable processes it is almost impossible to create and implement an appropriate reaction to this instability.

Active control

Which brings me to the final organizational benefit I want to discuss and that is an improved ability to actively control processes. The Lean Six Sigma methodology shortens cycle times and puts in place real-time data based control plans and systems. With short cycle times and data-based control systems, the operators and process managers can make decisions that immediately impact process performance. This improves performance, improves employee morale, and improves agility. The operators understand how their work impacts the process performance and they get rapid feedback. The operators are less likely to feel that they are victims of the process since they are now involved in directly managing the process and improving it. With short cycles and active control, the organization can quickly respond to opportunities in the changing marketplace. And short efficient processes that are documented with value stream maps and control charts are easier to update than complex undocumented processes.

Lean Six Sigma provides benefits for individuals within the organization who become Lean Six Sigma leaders. We will discuss the various leadership roles in more detail in a later section. First let’s identify some of the personal benefits you can expect when participating in Lean Six Sigma.

Personal effectiveness

Lean Six Sigma provides a structured problem-solving methodology that can be used to address any type of problem. Being able to find and fix problems will improve your ability to perform in any position and industry. The Lean Six Sigma methodology steers you through an organized process of inquiry, analysis, problem identification and solution creation. Many of the tools and techniques can be applied to everyday problems and issues. But even if you don’t use all the tools, the organized problem-solving approach will put you in control of finding and fixing your problems. I have used this approach when fixing problems at my house, with local charities I support, and of course in many different business settings.

Leadership opportunity

Lean Six Sigma is implemented through projects and projects have leaders. Leading a Lean Six Sigma project will often provide an opportunity for exposure to other functions and senior management. This exposure is in the context of someone who can find and fix a problem. Interacting with team members and managers will likely improve your communication and decision-making skills. The structure of Lean Six Sigma can help you to develop your project management skills. And of course being able to put on your resume that you led a project team that achieved cost savings, quality improvement, and cycle time reduction will only help you as you seek that next promotion or new opportunity.

Pay and promotability

Which brings us to the pay and promotability of Lean Six Sigma practitioners. Attaining belt certification is a valuable credential on your resume. Many job postings require that an applicant have a Lean Six Sigma credential. So, this will open the door for some promotions. In addition, within an organization, promotions are often based upon how you have demonstrated your leadership skills. Effectively leading a Lean Six Sigma project shows senior management and HR that you are ready for greater responsibility. The average annual salary in the USA for Lean Six Sigma Black belts is just under $100,000. The average for your industry and country will vary. However, it is safe to say that Lean Six Sigma certification will enhance your earning potential.

Industries and functions using Lean Six Sigma

Lean started in the process engineering department of an automotive manufacturer and Six Sigma started in the quality department of a high-tech system manufacturer. However, the methodologies have moved well beyond their roots in quality and process engineering. I have either participated on or coached Lean Six Sigma projects in virtually every business department including:

• Call Center
• Customer Service
• Design Engineering
• Field Sales
• Human Resources
• Maintenance
• Manufacturing Engineering
• Manufacturing Operations
• Process Engineering
• Purchasing/Sourcing

Lean has also moved well beyond the realm of manufacturing. Many industries have embraced Lean Six Sigma, and the list of companies using the methodology is much too long to be included here. In some cases the emphasis will be primarily on Lean, in some on Six Sigma, and in many it is the combination of Lean and Six Sigma.

• Agri-business
• Electronics
• Financial Services
• Higher Education
• Manufacturing
• Medical Devices
• Oil and Gas
• Pharmaceuticals
• Transportation

Lean Six Sigma belts

So far we have discussed the background of Lean Six Sigma, the principles embedded in Lean Six Sigma and some of the benefits. You are probably asking, when are we going to explain how it works? Well, now is the time. Let’s go through the key roles and responsibilities, the five-phase structure with gate reviews, and then do a quick overview of some of the more commonly used tools and techniques.

Lean Six Sigma has adopted the roles from the Motorola Six Sigma methodology, which borrow the naming convention of the progression of mastery used within martial arts. Some organizations have their own levels and definitions of mastery. However, I will be describing the most commonly found levels in use today. You may have heard of Lean Six Sigma belts - these are the Yellow Belt, Green Belt, Black Belt, and Master Black Belt. Each of these roles are expected to have training, and in many cases certification appropriate to their role.

In the early years of Lean and Six Sigma, every organization established its own standards with regards to methodology and tools and techniques. However, most organizations now rely on an independent certifying body for training and certification. The two most widely recognized organizations that provide certification are American Society for Quality (ASQ) and the International Association of Six Sigma Certification (IASSC). The GoSkills Lean Six Sigma courses are aligned with the IASSC Body of Knowledge. Let’s look at each of these roles in more detail.

What is Lean Six Sigma Yellow Belt?

An organization can have many Yellow Belts . These individuals are team members on a Lean Six Sigma project led by a Green Belt or Black Belt. They should be familiar with the structured methodology and the use of cross-functional tools and techniques.

• They will participate in all the project team meetings acting in the role of subject matter expert for their function or discipline. This role is performed in conjunction with their normal full-time job or position.
• A project will have as many or as few Yellow Belt members as are needed based upon the scope of the process being investigated and the nature of the problem.
• The training for a Yellow Belt normally focuses on the structure of the methodology and the use of the cross-functional problem-solving tools and techniques.
• The detailed Lean and Six Sigma analysis is normally handled by the Green Belt or Black Belt who is leading the project. However, the Yellow Belt team members are often the ones who collect the data used in analysis and help to interpret the results of the analysis.
• The Yellow Belt team members will also lead the implementation of the solution within their respective function or discipline.
• It is common for a person with Yellow Belt certification to be a member of multiple Lean Six Sigma project teams.

What is Lean Six Sigma Green Belt?

An organization will have multiple Green Belts. The Green Belt role is normally that of a project leader. The Green Belt is typically working on Lean Six Sigma projects that would fall within their area of expertise and responsibilities. These individuals know the Lean Six Sigma methodology and structure. They are also able to apply the Lean analysis tools and the statistical techniques commonly used with Six Sigma.

• These individuals lead small projects or projects that are focused on just one function. This role is normally performed in conjunction with another full-time position.
• Most Green Belts are leading a project that is associated with improving some aspect of their business processes. In some cases, a Green Belt may be assigned to a large cross-functional project being led by a Black Belt.
• Large cross-functional projects often have multiple analyses occurring simultaneously and a Green Belt will lead each of those efforts.
• As project leader, the Green Belt is responsible for ensuring that appropriate Lean Six Sigma tools and techniques are used at each phase on the project.
• This individual will normally lead the presentation and discussion of the project at the phase gate reviews. Because this individual is often the only person on the project who has been trained in the Lean analysis techniques and the statistical Six Sigma techniques, they will conduct these analyses.
• The Green Belt is not the subject matter expert on all aspects of the process or product, but they often are the expert on some portion of the process or product. As such they must bring their subject matter expertise to bear in the same way in which a Yellow Belt functions. However, the Green Belt is not expected to be an expert on all aspects of the advanced Lean Six Sigma tools and techniques. When they run into problems, they turn to their Black Belt for advice and coaching.

What is Lean Six Sigma Black Belt?

An organization will often have multiple Black Belts. The Black Belt role is that of subject matter expert on Lean Six Sigma for a function or location within the organization. These individuals lead large cross-functional projects and serve as coaches for the Green Belts in that department or location. This is normally a full-time position.

Black Belts know not only know how to apply the methodology and tools, they are the trainers and coaches for the Green Belts and Yellow Belts within the organization. A typical day will include:

• Conducting a team meeting for one of the project they are leading;
• Meeting with several Green Belts to review their progress and provide coaching for their next steps;
• Performing value stream or statistical analysis with data from one of the projects they are leading;
• Provide training on the use of Lean Six Sigma within their organization for Yellow Belt and Green Belt candidates;
• Meet with organizational stakeholders to discuss status of projects and identify problems or issues for future projects.

As you can see, the individual is usually expected to lead several projects simultaneously while acting as coach for a handful of Green Belts who are leading their own projects. The projects being led by Black Belts are usually large cross-functional projects. As project leaders they must plan and organize the work. What is often the most challenging aspect of those projects is to work with the stakeholders from the various functions. In many organizations, the Black Belt role is reassigned every year or two so that multiple individuals can become adept at all aspects of the Lean Six Sigma methodology.

What is Lean Six Sigma Master Black Belt?

The final level is that of Master Black Belt. Most organizations will have only one Master Black Belt, someone who is normally a senior individual responsible for managing the Lean Six Sigma initiative within the organization. This is a full-time position. Many times this Master Black Belt reports to the C-level champion for the Lean Six Sigma initiative.

• From a training and certification standpoint, this individual has the same credential as a Black Belt. However, the role and responsibilities are different.
• The Master Black Belt is not managing projects, rather they are managing the initiative.
• The Master Black Belt is normally working closely with senior leadership to determine how many Black Belts and Green Belts are needed and which functional departments or locations should get them first.
• The Master Black Belt normally maintains a status report on the portfolio of Lean Six Sigma projects; the active ones, the completed ones and the proposed ones. As such they are able to assess the impact of the overall program on the organization and they can prioritize the improvement efforts based upon the organization’s strategy.
• These individuals also work with HR to maintain the training records of all the Yellow Belts, Green Belts, and Black Belts in the organization.
• If an organization is small, or if the Lean Six Sigma initiative is small within the organization, the role of the Master Black Belt will be assumed by one of the organization’s Black Belts.

Five phases of Lean Six Sigma – DMAIC

Lean Six Sigma projects follow a structured methodology, based upon five phases. The five phases are represented by the acronym DMAIC – which stands for Define, Measure, Analyze, Improve, Control.

How is the Lean Six Sigma DMAIC process defined?

Each phase has an organizing premise or question that must be addressed. Once the question is satisfactorily answered, the project can proceed to the next phase. The duration of the phase is based upon the information and data that is available. Normally at the end of each phase there is a phase gate review with the stakeholders and one or more Black Belts. Let’s take a look at each phase in more detail.

The Define phase is the first phase of the project. The key question that must be answered is, "Have we defined the problem from a business perspective?" Normally a Green Belt or Black Belt project leader is selected and provided with a high-level description of the problem. Some Yellow Belt project team members may also be identified at that time. The project team needs to get input from stakeholders and customers to understand the problem from their perspective. During this time, they are quantifying what the customers consider to be critical quality expectations.

With an understanding of the problem from the business and customer perspective, the boundaries for the process - and any product or service that is delivered - can be determined. While a preliminary project team may be in place in this phase, the determination of the boundaries on the process will often dictate which functions need to support the project with subject matter experts. During this phase, those subject matter experts who are new to Lean Six Sigma will often receive Yellow Belt training. This phase often ends with the development of a project charter that identifies the problem from the customer perspective, the processes to be analyzed, and a goal for performance improvement.

The Measure phase is the second phase of a Lean Six Sigma project. In this phase the baseline condition is established by measuring the current performance of the process, product, or service with respect to the critical quality attributes identified in the Define phase. The question that is asked in this phase is, "Do we understand the work and flow of each of the steps in the current process and have we measured the process performance at each step?" If the process is not well documented or controlled, this will likely be the longest phase and requires the most work.

The process must be defined to determine the flow of each step. Each step is then measured for time, quality, and any other attribute that was important to the customer. Often the appropriate measurement systems do not exist to collect this data, so a measurement system will need to be developed and verified so that it provides accurate and complete data. The subject matter experts on the team from the various departments and functions are closely engaged in this phase to identify the process steps and to develop and deploy an approach for measuring performance. By the end of this phase, the problem experienced by the customer should be quantified with process data, and an accurate assessment of the current or "As-is" state for the entire process has been determined.

The Analyze phase is the third phase of a Lean Six Sigma project. In this phase, the process and product data are analyzed to determine the true root cause or causes of the problem the customer has experienced. The key question to be answered is just that, "Have we clearly identified the problem and determined the true root cause(s)?" It is at this stage that the project leader applies the Lean analytical tools and the Six Sigma statistical hypothesis testing techniques to determine the root cause. The project leader is expected to be able to mathematically show that the root cause has been identified. While the analytical and statistical techniques are rigorous, the math involved is usually very straight-forward, especially if a statistical analysis application is used such as Excel’s Analysis Tool Pak or Minitab.

Often the data collected during the Measure phase is sufficient for the analysis. However, in some cases, the analysis will point to an area requiring further study and additional data may need to be collected. Which analytical tool or technique is used will depend upon the nature of the problem or defect from the customer perspective and the types of data that are available for analysis. Often during this phase, a detailed problem statement will be completed based upon the results of the analysis. The team must guard against preparing a detailed problem statement before this step. Otherwise there is a good chance they will assume the wrong problem, which will lead to confusion and misdirection on the team when they begin to create a solution in the next phase. By the end of this phase all team members should be in agreement that the sources of the problem are now known and understood.

The Improve phase is the fourth phase of a Lean Six Sigma project. Teams often want to jump to this phase immediately without thoroughly completing the first three phases. When that occurs, the team usually creates an improvement that addresses a symptom without getting to the root cause. The goal for this phase is to create a solution to the problem that eliminates or contains it. The question being answered is, "Have we created a viable solution for the problem that is ready to be implemented?" Depending upon the nature of the identified problem, different team members will play a larger or smaller role in the creation of the solution.

During this phase, the solution is developed and tested. Depending upon the nature of the solution, this is often the most expensive phase. The "To-Be" process is developed and documented. In many cases, the new process requires changes in equipment, software, or procedures. Once again data is relied upon to be certain the solution has effectively addressed the problem, which normally means that a statistically significant number of operations are performed to collect that data. A trap the team can easily fall into is to prematurely celebrate a "random success." The solution must be thoroughly tested and the accompanying training and implementation materials developed and ready to be deployed. By the end of this phase, the solution is ready.

The Control phase is the final phase of a Lean Six Sigma project. In this phase the solution is fully deployed. The phase does not end until the solution is stable and all aspects of the business that are affected by the change are operational. The question being answered is, "Have we established a "new normal" that has eliminated or controlled the problem the customer experienced?" All members of the project team are involved with the implementation to be certain that any changes in their department are fully implemented. The phase continues until the process has demonstrated stability in performance. This may occur within a few days or may take several months.

A control plan is normally set in place for monitoring the process, product or service. The control plan includes threshold measurements for acceptable performance and corrective action steps to be followed if the performance degrades. This control plan is one of the keys to ensuring the improvement is permanent and that the process does not revert back to its prior state. In most cases, the control plan will include statistical process control . A major aspect of the work in this phase is often the updates of documentation in associated processes such as training processes, business information systems, and management review. This phase is completed when the operators and managers of the process no longer require support from the project team.

We have focused on the role of the project leader and the project team. However, senior management and the process stakeholders also have a role in the Lean Six Sigma methodology. These individuals, along with one or more Black Belts, will conduct the Phase Gate reviews. The reviews can be done in a face-to-face presentation, a virtual presentation, or through the submittal of a report that is reviewed and approved by the stakeholders and Black Belts. Which approach is used depends primarily on corporate culture and team logistics. These reviews occur at the end of each phase. A review has three purposes:

1. Review the work of the preceding phase to ensure that it was done with the appropriate Lean Six Sigma rigor. If this is found to be inadequate, the team will need to repeat portions of the work and come back for a new Phase Gate review. The Black Belt in the review will coach the team on the performance of the areas of weakness.

2. Review the answer to the phase question and the supporting data or documentation, to ensure it addresses the customer need. If the data does not support the answer, the reviewers should direct the team to continue in this phase until they have answered the question.

3. Establish any ground-rules or boundaries associated with the next phase, based upon the results of the preceding phase. Examples would be to set a time window for collecting data in the Measure phase or a capital budget limit for a solution to be developed in the Improve phase.

Reviewers need to be familiar with the Lean Six Sigma methodology and the structured approach to problem solving. They can easily derail a project team by asking the wrong question for the given phase. For instance, asking a team to identify the root cause of the problem during the Measure Phase Gate review will force them to jump to conclusions. That question should not be asked until the Analyze Phase Gate review. The Black Belt who is part of the review team should ensure the reviewers are aware of what questions the team should be prepared to answer, and which questions are not appropriate for that Phase Gate review.

The reviewers often include senior leaders from the organizations or departments with responsibility for the process being analyzed. If the team is encountering resistance to their activities or need special access or support, to conduct the next phase of the project they should be requesting that from the reviewers. An example might be to have access to certain data records or to have operators support a measurement systems analysis of the testing methodology. The response of the reviewers to these requests is a signal to the rest of the organization of the importance of the Lean Six Sigma initiative.

Lean Six Sigma tools and techniques

Now that we have covered the structure and process of the Lean Six Sigma methodology, let’s look at the tools and techniques. Many of these tools and techniques were in use long before the Lean Six Sigma methodology was formulated, and have been incorporated into this methodology. One of the powerful aspects of Lean Six Sigma is that multiple tools are available for use in each phase. A team can then choose the tool or technique that best fits their unique situation. Organizations will often have a favorite set of techniques based upon their corporate culture or historical preferences.

These tools and techniques are organized based upon the types of analysis in which they are used. Many of these could be used in multiple phases of a Lean Six Sigma project, depending upon the problem and analysis being conducted.

Process analysis tools and techniques

Process analysis tools and techniques are often associated with the Lean portion of the analysis. They help to describe the process and understand its efficiency.

• Process Map – a graphical display that shows the interactions between all process steps and decisions points within a process. Each step is a separate item on the process map.
• Value Stream Map – a special case of a process map that shows the primary flow through a process when every step goes as planned (no rework or branch points). It is the set of steps that create the customer value from the process.
• As-Is Process – this the process map or value stream map that shows all the steps in the process as it is actually occurring in the current business environment. This is not necessarily the same as what is documented in the procedures.
• To-Be Process – this is the desired process map or value stream map after the problem solution has been implemented. This is often reflected in revised process documentation that is released as part of the implementation.
• Data Boxes – these are boxes on a process map or value stream map that are associated with each step. The data box is used to record the metrics associated with that step in the process such as cycle time, value-added time, yield, inventory, or resources.
• TAKT Time – this is a time measure associated with the process. It reflects the amount of time allowed for each process step that ensures the process can meet the customer demand.
• Value Added Time – this is the portion of processing time within a step where an element of customer value is being created on a single item flowing through the process. The value-added time is normally a very low percentage of total time within a step, and is zero for many steps.
• Roll Throughput Yield – this is a calculation of the likelihood that an item will pass through every step in the process being correctly processed on the first pass through that step. It is calculated by multiplying all the step yield values from a value stream map.
• Work-cells – this is a process structure that is often used to speed up flow through the process. All process steps are arranged together in a work cell which reduces time wasted in handoffs between steps.
• Kanban – this is a visual scheduling approach used in process management where a step provides a signal to the preceding step showing that it is ready for the next item. This approach minimizes inventory and ensures each step is working on the item that is currently most important for that step to process.
• Visual Control – this is a set of signaling approaches that allows operators to see where process bottlenecks are occurring and to assist in the actions to relieve those bottlenecks. This allows for real-time process management.

Visual analysis tools and techniques

Visual analysis tools and techniques are used with virtually every problem-solving methodology. These techniques can be used in multiple phases. Their value is that they are quick and easy to understand. They are also excellent communication techniques with senior management and the operations or organizations that will be affected by the solution.

• Histogram – this is a vertical bar chart that shows the relative size of different categories of instances or occurrences. It is used to identify what attributes are the largest contributors to a problem.
• Pareto Chart – this is special version of the histogram. It is organized so that the largest category is first, the second largest is next, and continues on to the smallest category. If provides focus for improvement.
• Fishbone (Cause and Effect or Ishikawa) Diagram – this is a graphical depiction of all the possible causes of the problem, organized into logical categories. This becomes a roadmap for investigation to determine which of the causes contributes to the problem.
• Scatter Diagram – this is a plot of two attributes associated with each data point. One attribute is shown on the vertical axis and one on the horizontal axis. The plot will reveal whether there is correlation between the two attributes.
• Box Plots – this diagram shows the spread of data for a parameter and the nature of any central tendency. The center half of the data points are shown in a box with a line at the value of the midpoint in the box. The outer half of the data is split into the upper and lower portions and shows the extremes and overall data spread.
• Run Chart – this is a diagram of the sequential values for a parameter as a process is operating. The values are either each successive product or result or they are values collected at set times during process operation.
• Pie Chart – this is a diagram that shows the relative size of categories of a parameter. They are shown as slices of a "pie" representing their percentage. It is often used for "before" and "after" comparisons.
• Check Sheets – this is a diagram showing what is to be measured on a product, process or service. It will often include the measurement technique.
• Quality Function Deployment (QFD) – this technique is a diagram of how the prioritized customer needs are deployed across product and process parameters. It is often used to set performance goals and identified both missed opportunities and wasted activity.
• Solution Selection Matrix – this tool is a matrix that compares solution options across several criteria. When done using plus and minus symbols, it becomes a Pugh Concept Generation Matrix. The other option is to assign scores to each option and weights to the criteria. The matrix can then be used to evaluate the options to select the one with the highest score.
• Bottlenecks – these are areas in a process map with tangled flow or steps where inventory accumulates. Bottlenecks are collectors of waste. There is waste associated with slow moving inventory and waste associated with the extra management needed to accommodate the bottleneck.
• Poka Yoke – this is a set of disciplines that embody the principle of error-proofing. Through the design of the product or process, checks are embedded to prevent mistakes from being made or to make them immediately obvious so they can be fixed.
• Five "S" Disciplines – these are a set of workplace organization disciplines that are visual in nature and provide an indication of whether the workplace is operating smoothly. Deploying the Five "S" Disciplines improves quality and employee safety and morale.

Statistical analysis tools and techniques

The statistical analysis tools and techniques are often associated with the Six Sigma portion of the analysis. The statistical tools help us to make sense of the data and to determine what is significant and what is not. The use of statistical software such as Excel Analysis Tool Pak or the Minitab application has minimized the amount of mathematical computation that the team members must do. However, they still need to understand which statistical techniques to use in each situation and how to interpret the results.

• Process Capability – this is a statistical ratio that compares the normal process variability with the customer or specification limits. It is expressed with process capability indices of Cp, Pp, Cpk, Ppk, or process sigma. The process capability ratio is an excellent predictor of whether the process will be able to deliver defect-free results.
• Descriptive Statistics – these are statistics that describe the normal behavior of a measured parameter within a process or product. It includes the mean, median, mode, and standard deviation.
• Inferential Statistics – these are statistics used to relate the statistical performance of a sample to the statistical performance of the larger data population that the sample represents. These statistics are based upon the sampling approach used and include confidence interval and confidence level.
• Measurement System Analysis – this is a comprehensive analysis of an inspection or test systems ability to correctly determine a measured value within a process or product. It includes an assessment of accuracy, precision, stability, linearity, and discrimination.
• Gage R&R – this is a subset of a typical measurement systems analysis that focuses on the precision of the measurement system. It is a set of experiments using products or processes with predetermined known values and measuring them to determine whether the measurements system will consistently assign the same values.
• Hypothesis Tests – These are statistical tests of a data set to determine whether an assumption about the data can be verified or not. Typically, it is used within Lean Six Sigma to determine if data samples are similar or if there is a statistical difference. If data sets can be shown to be dissimilar, that is an indication that the factor which separates the two data sets has a significant impact on process or product performance. There are many different statistical techniques used depending upon whether the data is normal or non-normal, continuous or discrete, and the number of data sets or parameters being evaluated.
• Correlation – this is a hypothesis test that is used to show whether two continuous data parameters are related, and how they are related.
• Regression Tests – this is a hypothesis test that determines the mathematical relationship between two or more continuous data parameters.
• T Tests – this family of hypothesis tests is used to compare the descriptive statistics of two data samples to determine if they are similar.
• ANOVA – this technique is used to compare the descriptive statistics of two or more data samples to determine if they are similar.
• Tests of Proportions – this family of hypothesis tests is used to determine if two samples of discrete data are similar.
• Chi-Square Test – this technique is used to determine if two or more samples of discrete data are similar.
• Design of Experiments – this is a statistical technique for creating a set of tests with test specimens that are designed to include or exclude certain features and with attributes set at the minimum or maximum level. Based upon the set of experiments, a best case design can be created with the appropriate design features and design targets. This technique is often used when creating a new product or process during the Improve phase.
• Control Charts – these are charts that track the performance of selected process or product parameters and determines whether the variation that is displayed is due to common causes or special causes. There are many different control chart designs, based upon the characteristics of the data and the attribute being measured. These charts are normally used in the Control phase as means of ensuring the improved process performance is sustained.

Project and team management tools and techniques

Lean Six Sigma projects must also be able to interact with stakeholders and customers. There are several techniques that have proven effective in this regard. Some of these are based upon understanding the perspective of external stakeholders and some of these are useful for organizing and communicating with internal stakeholders, such as team members.

• Critical to Quality (CTQ) – these are the process, product, or service parameters that are the attributes of customer value. They are determined by the stakeholders, not the project team.
• Project Charter – this is a project management document used to authorize the project and provide boundaries on the scope of the activity. The format varies from organization to organization.
• In-frame/Out-of-frame – this technique is used to clarify boundaries for a project team. The scope of the project is described in the frame. Areas that are not to be included in the analysis are listed as out-of-frame.
• SIPOC – This stands for Supplier, Input, Process, Output, Customer. It is a technique used to define the limits of the process that is being analyzed and to clarify the stakeholders for the process.
• Cross-functional team – this refers to the makeup of the Lean Six Sigma team. Normally there is at least one representative from each function who has responsibility for performing activities within the process being studied.
• Team decision-making – this is a set of practices used by teams to reach consensus when making decisions. Although many of the team conclusions are determined by the results of the data analysis, there are still decisions to be made in team operation, solution development, and implementation planning.
• Stakeholder management – this is a set of practices that are used to identify the key stakeholders for the Lean Six Sigma project. The key performance goals and communication pattern are also established for each stakeholder.
• Culture change management – this is a set of communication and implementation practices that focus on building buy-in and support for changing processes and work practices. This is often needed during the Improve and Control phases to ensure the solution is viable and sustainable.
• Implementation planning – the implementation of the solution is often a project as big or bigger than the Lean Six Sigma analysis project. This is a set of project management practices used to plan and execute a project.

How does Lean Six Sigma work?

In order to illustrate how Lean Six Sigma works, I will use the methodology to solve a hypothetical problem. Let me set the stage:

Some mornings when you prepare to leave home for work, you can’t find your keys. Searching causes delays and you miss your train or bus. Even worse, sometimes you take your spouse’s keys and then you can’t unlock the office when you arrive. Now you need to wait for someone else to arrive to open the office. Not to mention, your spouse has the same problem when they get to work. The problem has occurred multiple times and your boss has remarked about it. Something must be done to ensure it does not happen again.

Let’s apply Lean Six Sigma methodology and see where it leads us.

Let’s start by considering this from the customer perspective. You and your spouse are the primary customers of this process. Your goal is twofold: a) leave for work on time, and b) have the correct keys with you when you leave for work. This leads to one primary CTQ, the keys are in a known location and you can grab them and take them with you when you leave home in the morning. Based upon the In-Frame/Out-of-Frame, you decide to limit the process to what is done with keys the night before and in the morning. You will not include everything else you do to get ready for work in the morning such as breakfast, showering, and getting dressed – except to the extent that they impact the keys. The goal for the project Charter is to create and implement a process that results in the immediate acquisition of the correct keys in the morning when leaving for work.

In this phase you create a process map that shows all the possibilities for what happens to the keys at night. The process starts with arrival at home and ends with arrival at the office the next morning. The process has different branches depending upon whether it was a weekday, weekend or holiday, whether you went out that evening or stayed in, and whether you have inclement weather requiring additional preparation to leave, such as finding an umbrella or a cold-weather coat. In creating the map, you realized that the process on weekends and holidays varied so widely you could not even map it, but the process during the week was relatively stable. This is your As-Is process map.

You applied a time metric to each step and a success or yield metric. Of course, many of the steps, especially those spent searching in the morning, had no value-added time associated with them. In fact, the only value-added steps were the step of placing the keys on your desk when arriving home and picking up your keys in the morning.

A challenge you faced with the process mapping and measurement was to define a pass or fail condition for each step. In some cases it was obvious, in others you had to think through the purpose of the step to determine the desired outcome. You then collected data for four weeks. To do this you created and used a check sheet every night at bedtime to determine what you had done that evening when arriving home from work and then noted how much time each step required. You also created a check sheet for your activities in the morning, but you normally did not complete that until you arrived at work. Finally, you documented what you did with the keys on each day of the weekend and on the one holiday that fell within that four-week period.

A significant challenge in the data collection was the Hawthorne Effect . This is the name given to the condition where the measurement of a parameter changes what people do. If they know they are being measured, their behavior changes to optimize the measure. By completing the check sheet every night, you were changing your behavior. So you were careful that even if you realized at night that the keys were not in the correct place on your desk, you did not go then to find them, but waited until the morning as would normally occur.

Now that there is data, the analysis can begin. An obvious problem is that there is no process defined for weekends and holidays. But even during the weekdays you find that your process is unstable. There is minor common cause variation most of the time, but on six of the weekdays there was a major problem finding the keys. You never took your spouse’s keys by accident during the four weeks; but that has only occurred twice in the past six months, so you aren’t able to draw any conclusions about that type of defect.

You create a Fishbone diagram to determine the root causes, and you brainstormed seventeen possible causes for uncertainty in the location of keys in the morning. (Even though you were brainstorming and normally would not reject any ideas, you choose not to include the intervention of space aliens as one of the causes – although it was suggested by your spouse.)

Based upon your analysis, you find that five of the possible root causes could have contributed to the six occurrences of the problem in your data set.

• There is no designated place where keys are to be kept.
• When arriving home with hands full of shopping bags, the keys are often dropped where the packages are unloaded and become mixed with the items from the store.
• When arriving home with an immediate request for attention – such as the phone ringing – the keys are dropped at the location where the attention is needed.
• When arriving home with extra articles of apparel due to inclement weather, the keys may end up in the closet or the pockets of a coat.
• Sometimes, when someone sees keys in an unusual place, they move them to a place they believe to be a better location without telling their spouse the keys were moved.

You dig deeper into the analysis of what happens when you arrive at home using the ANOVA. In doing this you find that there is a major difference in what happens to your keys when there has been inclement weather.

It is doubtful that weather causes keys to change location by themselves, so you must do something different when there is bad weather. This points to the need to understand your process for removing and storing your inclement weather apparel. This points to a process problem. You determine that there are two contributing root causes.

• Process: There is no defined process for what to do with keys on the weekend.
• Process: There is no defined process step for storing keys when returning home.
• Root Cause: When arriving home with extra articles of apparel due to inclement weather, the keys may end up in the closet or pockets of a coat.

Now it is time to create a solution. First you and your spouse decided on the process changes that need to occur, and created a selection matrix to assess the options. One idea was to place a large hook on the door so that the keys could be hooked there whenever someone returned home. However, that option was not very decorative. A second option was to chain the keys to your belt or purse, but that was rejected because chains didn’t fit your style of dressing. A third option was to connect an RFID tag to the key chain and then install an app on the computer that would tell you location of the keys. While this did not create decorative or fashion concerns, the cost was higher than you were willing to pay. Using the selection matrix, you finally decide to place a small magnetic bowl on your desk that would hold both your keys and your spouse’s keys.

This bowl fits the desk décor and created a "home" for the keys. Then a process step was added for arriving home. Following removal of inclement weather apparel (if any) the keys were to be immediately placed in the bowl. This same practice was to be adopted for the weekends. Whenever anyone returned home, the first step was to place the keys in the bowl. This was the "To-Be" process.

Because the bowl was prominently placed on the desk, it also served as a Poka Yoke reminder of key status. If either of you were home, the bowl should not be empty. If both of you are home, both sets of keys should be there. This solution addressed all four of the issues that had been found in the Analyze phase. A process was now defined for both weekdays and weekends. This process accounted for inclement weather apparel and it designated a place where misplaced keys should be taken. You determined to add one more thing to further Poka Yoke the solution. You and your spouse have different color fobs attached to your keychains. The two sets of keys are now easily distinguished.

You and your spouse try the new process for a week and find that it is easy to follow on the weekdays, but you still had trouble remembering to put the keys there on the weekend. So, an additional step was added to the process. This step was that every evening when you went through the house to check that the doors and windows were locked, you also checked that the keys were in the bowl. That check was easily added to the "go to bed" process since during that process you always checked the computer on the office desk.

In this example, this phase will be easy to complete. You don’t have a large cross-functional organization to change. But it does involve the change in habit patterns for you and your spouse, so the process needs to be monitored to ensure it is followed. You create a control plan.

The keys are checked every night to be certain they are in the bowl. The response plan is that if the keys are not in the bowl, you and your spouse immediately get up to search for the keys and place them in the bowl before retiring to bed. Approximately three weeks after fully implementing the change, you and your spouse returned late one weekend night after attending a gala party. You were exhausted and just wanted to go to bed. However, when doing the "go to bed" process, you recognize that a set of keys is missing from the bowl. Although tempted to ignore the problem for the night, you and your spouse do a quick check and find the keys with the outer garments you wore to the party. Placing them in the bowl, you are now able to go bed with a clear conscience and peace of mind.

The plan was implemented and the misplaced key problem was eliminated. Although the new process had two additional steps, it effectively eliminated the frantic loop of looking for keys in the morning. The overall time was reduced, efficiency was increased, the error rate dropped to a non-existent level, and customer satisfaction was enhanced.

Here are several important takeaways from our look at Lean Six Sigma.

First, Lean Six Sigma is a structured problem-solving process using data that transforms the "lucky guess" problem-solving approach that is often used in organizations today. The structured process guides the team through the steps they should follow, and the reviews ensure that they are not cutting corners.

Second, Lean Six Sigma contains many tools, but the tools do not rule the team. The Black Belt and Green Belt project leaders select the appropriate tool for the situation. The tools are there to assist the team in their analysis, not constrain them.

Finally, the goal is an improved process, product or service that better meets the customer expectations. Lean Six Sigma is not about the process or the tools, it is about the customer. A project success is declared when waste and variation are eliminated or reduced and customer value is enhanced.

Ready to learn more about Lean Six Sigma and prepare to get certified? Browse our IASSC accredited Lean Six Sigma certification online courses.

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What Is Lean Six Sigma?

Lean Six Sigma combines lean manufacturing and Six Sigma to help organizations improve their processes and reduce waste. Here’s why it’s effective.

Lean Six Sigma brings together principles from lean manufacturing and Six Sigma.  Lean manufacturing is a philosophy that emphasizes the elimination of waste and the improvement of production flow through collaborative team effort. Six Sigma is a data-driven methodology that uses statistical analysis and problem-solving tools to identify and eliminate defects as well as process variations. Lean Six Sigma combines these methodologies to increase organizational efficiency.

Why Is Lean Six Sigma Important?

The combination of lean and Six Sigma methodologies provides a comprehensive approach to process improvement that can help organizations streamline their operations, reduce costs and improve quality, thereby leading to significant improvements in efficiency and customer satisfaction.

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Lean Six Sigma Techniques

Lean Six Sigma uses a variety of techniques to improve processes and reduce waste.

Value Stream Mapping 

VSM is a tool we use to identify and eliminate waste in a process by mapping out the entire value stream, from the start of the process to the end.

DMAIC 

DMAIC (Define, Measure, Analyze, Improve, Control) is a problem-solving methodology used to improve existing processes by identifying and eliminating the root cause of problems.

What Are the 5 Phases of Lean Six Sigma?

The Lean Six Sigma methodology typically consists of five phases known as DMAIC, which stands for define, measure, analyze, improve and control.

Kanban 

Kanban is a visual management tool that helps manage and control the flow of work by using cards or other visual indicators to signal where tasks are within a given project workflow.

5S is a workplace organization methodology that aims to improve efficiency and productivity by creating a clean, safe and organized work environment.The term 5S stands for the five Japanese words that describe the steps involved in the method: seiri (sort), seiton (set in order), seiso (shine), seiketsu (standardize) and shitsuke (sustain).

Poka-Yoke 

Poka-yoke is a mistake-proofing technique used to prevent errors from occurring in a process by designing products or processes that make it impossible for errors to occur. We can accomplish this by implementing physical or visual cues that alert the worker to a potential mistake or prevent the mistake from happening in the first place.

For instance, most modern microwave ovens have a safety mechanism that prevents the oven from operating if the door is not properly closed. This ensures that the user will not accidentally turn on the microwave with the door open, which could result in injury. This is a perfect example of Poka-Yoke implementation that protects users from injuries.

Statistical Process Control (SPC) 

SPC is a technique used to monitor and control a process by using statistical methods to measure and analyze data . Control charts, process capability analysis and sampling plans are among these statistical methods used in SPC. 

Sampling plans help us determine how many samples of a product or process output we should take for analysis. The goal is to obtain enough data to make accurate inferences about the overall process performance while minimizing the cost and time required for data collection and analysis. 

Control charts help identify when a process is producing results that are outside of the expected range, which can signal the need for corrective action.

Process capability analysis involves calculating statistical metrics such as Cp and Cpk, which measure how well the process is centered and how much variation it produces. 

Root Cause Analysis (RCA) 

RCA is a problem-solving technique used to identify the underlying causes of problems by asking “why” until we reach the root cause.

Advantages of Lean Six Sigma

Improved quality.

• Increased Efficiency

Cost Reduction

Improved customer satisfaction, cultural change.

• Competitive Advantage

Lean Six Sigma methodologies are designed to improve process efficiency and reduce defects. By using data-driven analysis and process improvement techniques, Lean Six Sigma can help organizations improve product or service quality, which can lead to greater customer satisfaction and loyalty.

Increased Efficiency 

Lean Six Sigma helps organizations identify and eliminate waste, non-value-added activities and other process inefficiencies. These improvements help reduce process cycle times, increase throughput and reduce costs, all of which lead to greater efficiency and productivity .

By reducing defects and inefficiencies, Lean Six Sigma can help organizations reduce costs associated with rework, scrap and other forms of waste. This can result in significant cost savings and improved profitability.

Lean Six Sigma helps organizations focus on customer needs and expectations, which can lead to improved customer satisfaction and loyalty. By reducing defects and improving quality, organizations can increase customer trust and confidence.

Lean Six Sigma methodologies emphasize collaboration, data-driven decision-making, customer value and a culture of continuous improvement . 

The methodology encourages employees to constantly look for ways to improve processes, reduce waste and increase efficiency by promoting collaboration across teams. By breaking down silos and encouraging teamwork, it fosters a more positive and collaborative work environment.

Lean Six Sigma promotes data-driven decision making as it helps to establish a culture of continuous improvement. By regularly collecting and analyzing data on process performance, companies can identify trends and patterns that indicate areas for improvement. 

Competitive Advantage 

By improving quality, efficiency and customer satisfaction, Lean Six Sigma can help organizations gain a competitive advantage in the marketplace. This can lead to increased market share, revenue growth and improved profitability.

Lean Six Sigma Phases

1. define .

In this phase, we establish a project team. The team then works to define the project goals and objectives as well as identify the process to be improved. The team also clarifies the problem and the customer’s requirements.

2. Measure 

In this phase, teams measure and baseline the current performance of the process, collect data and develop a process map (or flowchart) to understand the process steps and potential areas for improvement.

3. Analyze 

In this phase, teams analyze data to identify the root cause of problems and process variations. The team may use statistical analysis and other tools to help them identify the most significant causes of process problems.

4. Improve 

In this phase, the team develops and implements process improvements by using the information gathered in the previous phases. The team may use lean tools to reduce waste, improve flow and make the process more efficient. The team may also use Six Sigma tools to reduce variation and improve quality.

5. Control 

Finally, the team monitors and sustains process improvements over time. During the control phase, teams focus on monitoring and sustaining the improvements achieved in the previous phase. The team also develops a control plan to monitor the process and take corrective action when necessary.

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DMAIC in Lean Six Sigma vs. Six Sigma

The DMAIC process in Six Sigma and Lean Six Sigma is essentially the same. However, there are some key differences in how we apply DMAIC in the context of Six Sigma versus Lean Six Sigma.

In Six Sigma, DMAIC is typically focused on improving the quality of a process by reducing defects and minimizing variability. The emphasis is on achieving statistical process control and improving process capability. The team may use statistical tools such as hypothesis testing, design of experiments and control charts to identify and eliminate sources of variation and improve process performance.

In Lean Six Sigma, we use the DMAIC process to improve both the quality and efficiency of a process by reducing waste and improving flow. The team may use lean tools such as value stream mapping, 5S and kaizen events to identify and eliminate non-value-added activities and streamline the process flow. The team may also use Six Sigma tools to reduce variability and defects and improve quality.

Another key difference is that Lean Six Sigma places a greater emphasis on the customer and their needs throughout the DMAIC process. Teams identify and analyze customer needs in the define phase, then monitor and measure customer satisfaction throughout the process. This helps ensure the process improvements are aligned with the needs of the customer and deliver value to the organization.

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Lean Six Sigma Belt Levels

Lean Six Sigma uses a belt system to denote different levels of expertise and responsibilities within the organization. The belt system is based on the martial arts belt system, where darker belts indicate a greater level of expertise. Each belt level has its own set of responsibilities and requirements for certification.

There are five levels of Lean Six Sigma belts.

White Belt 

This is the introductory level of Lean Six Sigma training and provides an overview of the basic concepts and principles of Lean Six Sigma.

Yellow Belt 

Yellow belt training provides a more detailed understanding of the Lean Six Sigma methodology and prepares individuals to participate in improvement projects.

Green Belt 

Green belt training provides a comprehensive understanding of Lean Six Sigma tools and techniques and prepares individuals to lead improvement projects.

Black Belt 

Black belt training provides advanced training in Lean Six Sigma tools and techniques and prepares individuals to lead complex improvement projects and manage improvement programs .

Master Black Belt 

Master black belt training provides the highest level of training in Lean Six Sigma and prepares individuals to be experts in the methodology and lead strategic improvement initiatives while mentoring and training others.

In addition to these belt levels, there are also Lean Six Sigma Champions who provide executive sponsorship and leadership for improvement initiatives, as well as Lean Six Sigma Facilitators who provide training and support for improvement projects.

Lean Six Sigma vs. Six Sigma

Lean Six Sigma and Six Sigma are two related methodologies that share the goal of improving business processes and reducing defects. However, there are some key differences between the two.

Six Sigma is a methodology that focuses on reducing defects and improving quality by using statistical analysis to measure and improve process performance. 

Lean Six Sigma, on the other hand, combines the principles of lean manufacturing and Six Sigma. In addition to the DMAIC process, Lean Six Sigma also includes lean manufacturing principles such as value stream mapping, 5S and Kanban to improve process efficiency.

The main difference between Lean Six Sigma and Six Sigma is that Lean Six Sigma places a greater emphasis on the reduction of waste and non-value-added activities, while Six Sigma focuses more on reducing defects and improving process quality. 

Another difference is that Lean Six Sigma is more focused on continuous improvement and cultural change, while Six Sigma is more focused on solving specific problems and implementing process improvements.

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Guide: Critical to Quality (CTQ)

Author: Daniel Croft

Daniel Croft is an experienced continuous improvement manager with a Lean Six Sigma Black Belt and a Bachelor's degree in Business Management. With more than ten years of experience applying his skills across various industries, Daniel specializes in optimizing processes and improving efficiency. His approach combines practical experience with a deep understanding of business fundamentals to drive meaningful change.

Critical to Quality (CTQ) is a fundamental concept in continuous improvement and quality management, particularly within Six Sigma and other similar methodologies. It focuses on understanding and defining the essential characteristics or requirements of a product or service that are vital to meet or exceed customer needs.

Rooted in the Voice of the Customer (VOC), CTQ involves capturing both explicit and implicit customer needs and expectations. The process of identifying CTQs is strategic, aiming to align product or service development with customer expectations, thus fostering enhanced satisfaction and loyalty. This alignment is crucial in building trust and reliability between the customer and the brand, as it ensures that products or services precisely resonate with customer needs.

What is Critical to Quality

Critical to Quality is a common method used in continuous improvement and quality management, particularly within Six Sigma activities and other quality-focused methodologies. Central to CTQ is understanding the characteristics or requirements of a product or service necessary to meet or exceed the customer’s needs. CTQs come from what is known as the Voice of the Customer (VOC), which is a term that is used to understand all the needs and requirements of the customer, both stated and unstated.

Identifying CTQs is not just a tick-box exercise; it is a strategic approach that should be taken to align the development of products or services with the expectations of the customers (their voice). This alignment is important if you want to enhance customer satisfaction and develop customer loyalty. This is important, as when a product or service resonates with the specific needs and expectations of the customer, this creates trust and reliability between the customer and the brand.

The importance of CTQs

CTQS is the method that connects and translates intangible customer expectations into tangible and measurable product or service specifications.

For example, in a coffee shop, customers frequently complain about long wait times. To address this, the shop translates this intangible expectation of “faster service” into a tangible Critical to Quality (CTQ) measure: “Customers should receive their coffee within 3 minutes of ordering.” This clear, measurable goal allows the shop to adjust its processes and staffing to ensure quicker service, directly addressing the customers’ primary concerns and enhancing overall satisfaction.

This translation is an important process. It involves converting customer needs, which can often be broad and ambiguous, into clear, objective, and quantifiable criteria.

Identifying CTQs

Identifying CTQ factors starts with a deep understanding of customer needs; these are usually gathered via surveys, interviews, focus groups, or direct feedback. This crucial step involves converting customer requirements, often vague or broad, into specific, measurable, and actionable quality specifications. By doing this, businesses can translate abstract customer expectations into clear, quantifiable criteria, ensuring that products or services are designed and refined to meet these defined standards, thereby aligning closely with customer expectations.

Developing a CTQ Tree

Step 1: capture the voice of the customer.

The first step in developing CTQs is capturing the voice of the customer. This is about understanding what the customer truly values from the product or service you are looking to offer. The VOC is the customer’s expectation, so we need to capture this from the customers by using methods such as surveys, interviews, and collecting direct customer feedback.

These should be structured with questions that can identify customers’ expectations, preferences, and experiences with a product or service.

Example: A coffee shop wants to improve customer satisfaction. They conduct surveys, gather feedback through comment cards, and interview regular customers.

Action: They ask questions like, “What do you value most in your coffee experience?” or “What improvements can we make to enhance your visit?” From this, they learn that customers care about the quality of the coffee, the speed of service, and the ambiance of the shop.

Step 2: Identify the Critical Needs

Once you have collected the VOC, the next step is to sort through the customer feedback and group feedback by themes or affinity to create categories of focus. At this stage, you will typically find that the customer’s expectations are generally broad and unmeasurable. However, identifying these needs is important and will form the foundation for developing specific quality requirements. 

Example: The coffee shop analyzes the collected feedback and identifies recurring themes.

Action: They notice that customers frequently mention the desire for quicker service, especially during rush hours, the consistent taste of coffee, and a comfortable seating area. These become the broad categories of focus.

Step 3: Breakdown the Needs into CTQs

These critical needs from the VOC then need to be broken down into more specific requirements, known as Critical to Quality (CTQ) requirements. This step involves a detailed analysis to translate general customers’ needs into explicit, measurable, and actionable quality criteria.

Example: The coffee shop needs to translate these broad needs into specific quality requirements.

Action: For the need for quicker service, a potential CTQ could be “reducing the average wait time to under 3 minutes.” For consistent taste, a CTQ might be “implementing a standard recipe for each type of coffee.” For ambiance, a CTQ could be “ensuring seating comfort and availability.”

Step 4: Develop the CTQ Tree

The next step is to develop a critical-to-quality (CTQ) tree. This involves placing the customer’s needs as the trunk of the tree, with the branches of the trunk representing specific and measurable CTQs. This tree structure is useful to visually see how broad customer needs are connected to detailed quality requirements. This process helps stakeholders understand the collection and relationship between what customers want and the specific quality attributes that need to be achieved (KPIs)

Example: The coffee shop creates a visual representation linking customer needs to specific CTQs.

Action: The tree’s trunk represents the broad needs: service speed, taste consistency, and ambiance. Branching out from these are the CTQs: average wait time, standard coffee recipes, and seating comfort. This helps visualize how each specific quality requirement stems from a core customer need.

Step 5: Define Performance Standards for Each CTQ

Finally, for every CTQ that is identified, performance standards or specifications should be created. These will be metrics that are quantifiable and set clear benchmarks for quality. They will define the level of performance that must be achieved to meet the customer’s expectations. Setting these standards is important, as they provide specific targets for product development, quality control, and continuous improvement efforts.

Example: The coffee shop sets measurable goals for each CTQ.

Action: For the CTQ of reducing wait time, the standard could be “95% of orders fulfilled in under 3 minutes.” For taste consistency, a standard might be “100% adherence to coffee brewing procedures.” For ambience, a goal could be “availability of seating 90% of the time during peak hours.”

This is the process for understanding customers’ needs. Following this, constant data collection will be needed to measure how well those needs are being met. Actions and continuous improvement is then needed to be deployed to ensure customers’ needs are met or even exceeded.

Implementing CTQs in Quality Management

Once CTQ factors have been identified and defined, it is important to integrate them into the existing quality management framework. This involves establishing systems and procedures that are designed to monitor and control these CTQs.

Step 1: Set Up Monitoring Systems

You may need to adapt or develop your monitoring systems to collect information and keep track of CTQs and the results vs customer expectations. This can involve setting up metrics in quality and monitoring software, implementing or modifying production line checks, or implementing new customer feedback channels.

Step 2: Creating Procedures for Control

Procedures then need to be defined that dictate how to respond when a CTQ standard is not met. These can include Response or Control Plans which state what action needs to be taken by who

Step 3: Regular Measurement and Analysis

Once the control plans are in place, regular measurements of CTQs are needed to ensure that the product or service consistently meets the established quality standards. This involves not just collecting data but also analyzing it to identify trends, potential problems, or areas for improvement.

Step 4: Feedback Mechanisms

Finally, it is important to establish methods for customers to provide ongoing feedback. This continuous loop of feedback ensures that the product or service CTQs remain relevant and can be adjusted to reflect the changing customer needs or market conditions. 

The implementation of Critical to Quality (CTQ) in quality management is a robust process that transforms customer expectations into measurable and actionable quality standards. It begins with capturing the Voice of the Customer, identifying critical needs, and breaking these down into specific CTQs.

Developing a CTQ Tree visually links broad customer needs to detailed quality requirements, helping stakeholders understand and meet key performance indicators. Finally, setting performance standards for each CTQ and continuously monitoring and adjusting them ensures that products or services consistently meet customer expectations. This comprehensive approach not only enhances customer satisfaction but also drives continuous improvement, leading to sustained business excellence and customer-centric growth.

• He, Y., Tang, X. and Chang, W., 2010. Technical decomposition approach of critical to quality characteristics for product design for six sigma .  Quality and Reliability Engineering International ,  26 (4), pp.325-339.
• Yun, E.K. and Chun, K.M., 2008. Critical to quality in telemedicine service management: application of DFSS (Design For Six Sigma) and SERVQUAL .  Nursing economic$ ,  26 (6).
• Koziołek, S., Rusiński, E. and Jamroziak, K., 2010. Critical to quality factors of engineering design process of armoured vehicles.  Solid State Phenomena ,  165 , pp.280-284.

Q: What is Critical to Quality (CTQ)?

A: Critical to Quality (CTQ) is a term used in the field of Six Sigma and quality management. It refers to the key measurable characteristics of a product, process, or service that directly affect customer satisfaction. CTQs are the specific attributes or specifications that need to be met to ensure high-quality deliverables.

Q: Why is understanding CTQ important?

A: Understanding CTQ is crucial because it allows organizations to focus on the aspects that truly matter to customers. By identifying and measuring the critical quality characteristics, businesses can prioritize their efforts and resources to improve those areas. This helps in achieving customer satisfaction, reducing defects, and enhancing overall product or service quality.

Q: How do you determine CTQs?

A: Determining CTQs involves a systematic analysis of customer requirements, expectations, and feedback. This can be done through methods like surveys, interviews, focus groups, or data analysis. By understanding customer needs, translating them into specific metrics, and aligning them with business goals, organizations can identify the CTQs that should be targeted for improvement.

Q: What are examples of CTQs?

A: CTQs can vary depending on the industry and the specific product or service. Some examples of CTQs include product dimensions, durability, reliability, response time, speed, accuracy, error rates, customer support responsiveness, delivery time, and cost. The key is to identify the characteristics that have a direct impact on customer satisfaction and align them with business objectives.

Q: How can CTQs be measured?

A: CTQs can be measured using various statistical and analytical methods. This may involve collecting and analyzing data related to the critical quality characteristics. Statistical tools like control charts, capability analysis, process capability indices, and customer satisfaction surveys can be used to assess and quantify the performance of CTQs.

Q: What is the relationship between CTQs and Six Sigma?

A: CTQs are a fundamental concept within the Six Sigma methodology. Six Sigma aims to minimize defects and improve quality by reducing process variability. CTQs help in identifying the key characteristics that need improvement, and Six Sigma provides a structured approach to achieve this improvement by using statistical analysis and process improvement techniques.

Q: Can CTQs change over time?

A: Yes, CTQs can change over time as customer preferences, market dynamics, and business goals evolve. It is important for organizations to regularly reassess and update their understanding of CTQs to stay aligned with customer expectations and remain competitive in the market.

Q: How can organizations use CTQs to drive improvement?

A: Organizations can use CTQs to drive improvement by setting targets or goals for each critical quality characteristic. By monitoring and measuring the performance of these CTQs, organizations can identify areas of improvement and take corrective actions. Continuous monitoring and improvement of CTQs help in achieving higher levels of customer satisfaction and delivering high-quality products or services.

Daniel Croft

Daniel Croft is a seasoned continuous improvement manager with a Black Belt in Lean Six Sigma. With over 10 years of real-world application experience across diverse sectors, Daniel has a passion for optimizing processes and fostering a culture of efficiency. He's not just a practitioner but also an avid learner, constantly seeking to expand his knowledge. Outside of his professional life, Daniel has a keen Investing, statistics and knowledge-sharing, which led him to create the website www.learnleansigma.com, a platform dedicated to Lean Six Sigma and process improvement insights.

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“Toolbox? We Don’t Need No Stinking Toolbox!” Is Six Sigma a New Set of Tools or a New Way to Employ Existing Tools?

Published: February 26, 2010 by Robert Tripp

In the debate about whether Six Sigma is something new, the arguments for and against revolve in part, around the set of tools used to execute a Six Sigma project. Is Six Sigma a new set of tools or a new way to employ existing tools? The answer lies somewhere in the middle.

Many of the tools used for Six Sigma also have proved useful in conjunction with TQM and other process improvement methodologies. While some of the tools are new to process improvement activities, it is important to note that Six Sigma also provides a new way to use existing tools. It is the combination of tools and the way they are employed that gives Six Sigma its competitive advantage.

But Six Sigma is more than just tools and a methodology. To ensure success, the application of Six Sigma relies on the traditional scientific method to examine processes and remove undesirable causes and their effects. Significant value is derived from the sequence of observation, hypothesis, prediction and testing that began as the hallmark of scientific inquiry in the time of Aristotle. Traditionally, scientific inquiries examine the processes of nature in order to characterize cause-and-effect relationships. Six Sigma, and to a great extent the entire spectrum of engineering sciences, takes these same concepts and applies them to man-made systems in order to characterize the cause-and-effect relationships in value-creation (i.e., business) processes.

Belts Essentially Acting as Scientists

Consequently, Six Sigma Black Belts and even Green Belts who lead projects are essentially acting as scientists to the extent that they employ the same thought processes. As a result, the same qualities that make successful scientists are those that make successful Six Sigma Black Belts, people who shift between the statistics and the problem with little or no effort. They constantly digest process data, generate questions, probe traditional thought, test everything with data and analysis, and shift those results back to real world applications. As Black Belts lead projects through the Six Sigma DMAIC methodology, specific skills are required.

Define Phase

Ability to observe and characterize general, systemic issues. This is basic business acumen and is a skill that is often brought to the Six Sigma world by Champions and process owners who directly feel the pain of problems in their processes. It is the role of capable Black Belts to utilize empirical observation and deductive reasoning to narrow a general systemic problem to a more focused issue that can be adequately addressed given the limitations of time, data, and desired impact. In doing so, Black Belts must first be able to recognize any cause-and-effect relationship as a process, or at least part of a process. From this point, Black Belts will be able to understand and communicate the issue in the language of a process. They have the ability to take a high level process and understand the relationships between the sub-processes that constitute the higher level process. They then take the sub-processes and break them apart and, due to the understanding at a higher level, are less likely to optimize a sub-process at the expense of the larger process, also know as single-point optimization.

Measure Phase

Skeptical reliance on empirical data. Once a focused problem is defined, further observations are necessary in order to understand and comprehend the nature of the specific problem, i.e., extent, impact, frequency, amplitude, inherent variation. All observations should be studied knowing that no measurement technique is perfect. All interpretations are subject to the observer’s frame of reference. The use of quantitative data analysis, as opposed to qualitative interpretation, can significantly reduce the analyst’s bias.

Analyze Phase

Ability to use logic to characterize cause-and-effect relationships. Through multiple iterations of testing and experimentation, capable Belts must apply further deductive reasoning to identify specific root causes of the effects noted in the original problem. The application of a few common principles are particularly important:

• Ockham’s Razor – Given multiple competing theories to explain the same result, put a priority on the simplest to develop hypotheses for testing. In a sense, this is like saying, “Keep it simple, stupid.” This sorting process, if followed, will prevent Black Belts from devising complex solutions and using exotic techniques to solve relatively simple problems. It still contains enough rigor to avoid the classic “brainstormed solution.”
• Hanlon’s Razor – This rule says, “Never attribute to malice what can adequately be explained by incompetence.” In other words, people make mistakes, do not assume they are failing on purpose. Look for issues in the process or system that allow or encourage mistakes. More times than not people do things for a reason, i.e., lack of understanding of consequences on down-stream processes, fear, random data from a poor measurement system, etc. By understanding those reasons, skilled Black Belts become more knowledgeable of the inadequacies of the process under investigation.
• Intellectual Flexibility – Truly understanding a process requires multiple cognitive skills such as rational, analytical, intuitive, aesthetic, creative and moral, to name a few. The belief that any one is the proverbial silver bullet is “intellectual bigotry.” And just as with any other form of bigotry, it is based in ignorance.
• Passion for Knowledge – Apprehending the true nature of a process is at once intellectually, decisively and spiritually liberating. Do not infer that Six Sigma is a secret society, a society with secrets or that it is some kind of esoteric path to enlightenment. It is not. However, discovering the truth in a sea of ignorance, apathy and ambiguity should bring good Black Belts personal satisfaction, even in the absence of monetary reward or other recognition – an aesthete of an efficient process.
• Intellectual Honesty – It is important for Black Belts to recognize and admit the extent to which the “truth” remains unknown. Aberrations or unexpected results must be reported and explained without fear of personal repercussions. The consequences belong to those who fail to report and chronically cannot explain. Furthermore, successful Black Belts will constantly question the extent to which inputs simply correlate with outputs versus a quantifiable true cause-and-effect relationship.

Children see with “new eyes.” That is because they do not look through all the experiential prisms adults do. Those prisms cause adults to interpret something rather just experience it. Skilled Black Belts have learned to use data to help them return to new eyes. They use data and statistics to assist them in objectively experiencing something. Without the baggage of previous experiences, events take on a much freer meaning. The new meaning is what they use to create new questions. Just as a child can endlessly ask why, Black Belts use statistics to analyze a set of data, draw a conclusion and formulate the next question. These questions are the compass that skillful Black Belts use to identify the trail of clues that lead them to the new solution. By exhibiting these characteristics, capable Black Belts are able to arrive at the vital few root causes of undesirable effects in their processes by way of an efficiently designed and executed Analyze phase.

Improve Phase

Inductive reasoning. With all the available information derived from their analyses, Black Belts must be able to effectively apply the knowledge gained from specific (often narrow) frames of reference to the broader context of their processes. Truly talented Black Belts are multi-lingual in that they speak the language of the process and the language of statistics. As any multi-linguist knows, it is hopeless to try to impress an audience which does not speak the language. That is particularly true when the language is statistics. Successful Black Belts move easily and fluidly back and forth between the two – statistics and the process. In this way, Black Belts can fuel the creative process for deriving solutions in a successful Improve phase.

Control Phase

Action and initiative. Much has been written about the intellectual characteristics required to be a successful Black Belt, but none of this is meaningful if Belts are not willing to perform the work necessary to make change happen. Execution , the book by Larry Bossidy, chairman and former CEO of Honeywell International, is entirely dedicated to the critical importance of implementation and institutionalization even beyond the purview of Six Sigma. A Six Sigma project that does not deliver becomes a waste of resources thereby increasing the cost of poor quality (COPQ) rather than increasing the efficiency of the process.

Scientific Thinking at Heart of Six Sigma Success

While Six Sigma teaches and relies upon the use of specific tools to execute the problem-solving process, the basic tendency towards critical, scientific thinking lies at the heart of its success. No set of tools, whether they are team facilitation methods, change management techniques or statistical/analytical applications, can substitute for basic cognitive characteristics. Consequently, Six Sigma is not just a toolbox. It is a way of thinking about the business, about processes, and about cause-and-effect relationships.

So if Six Sigma is not about the tools, why are tools such an important part of the curriculum? The answer to that is that use of the tools helps to develop the sense of critical thinking and scientific perspective necessary for successful problem-solving. Statistics, more than simply a branch of mathematics, is a way of viewing an environment.

This truth also speaks to the issue that, while specific tools are taught for application during specific phases of the Six Sigma sequence, an accomplished Black Belt will employ various tools at any phase, regardless of whether the traditional deliverables of a phase require use of such tools.

Though it may be different, refreshing, even liberating, Six Sigma is not entirely new. It seeks to innovate through the discovery of truth with refined, rational cognitive skills and the objective analysis of empirical data. It is a collection of tools. It is a methodology. It is a thought process that dissects the large picture into smaller parts and reassembles it into a more efficient configuration. And most of all, Six Sigma delivers uncommon results.

About the Author

Robert Tripp

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What Is Six Sigma?

Understanding six sigma, the 5 steps of six sigma.

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What Is Six Sigma? Concept, Steps, Examples, and Certification

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Six Sigma is a set of techniques and tools used to improve business processes. It was introduced in 1986 by engineer Bill Smith while working at Motorola. Six Sigma practitioners use statistics, financial analysis, and project management to identify and reduce defects and errors, minimize variation, and increase quality and efficiency.

The five phases of the Six Sigma method, known as DMAIC, are defining, measuring, analyzing, improving, and controlling.

Key Takeaways

• Six Sigma is a quality-control methodology that businesses use to significantly reduce defects and improve processes.
• The model was developed by a scientist at Motorola in the 1980s.
• Companies often use the Six Sigma model to increase efficiency and boost profits.
• Six Sigma practitioners can earn certifications modeled on the color belts used in martial arts.

Six Sigma is based on the idea that all business processes can be measured and optimized.

The term Six Sigma originated in manufacturing as a means of quality control. Six Sigma quality is achieved when long-term defect levels are below 3.4 defects per million opportunities (DPMO). 

Six Sigma has since evolved into a more general business concept, focusing on meeting customer requirements, improving customer retention, and improving and sustaining business products and services. Among its best-known proponents was the longtime General Electric CEO Jack Welch .

Six Sigma certification programs confer belt rankings similar to those in the martial arts, ranging from white belt to black belt.

The Six Sigma method uses a step-by-step approach called DMAIC, an acronym that stands for Define, Measure, Analyze, Improve, and Control. According to Six Sigma adherents, a business may solve any seemingly unsolvable problem by following these five steps.

A team of people, led by a Six Sigma expert, chooses a process to focus on and defines the problem it wishes to solve.

The team measures the initial performance of the process, creating a benchmark, and pinpoints a list of inputs that may be hindering performance.

Next the team analyzes the process by isolating each input, or potential reason for any failures, and testing it as the possible root of the problem.

The team works from there to implement changes that will improve system performance.

The group adds controls to the process to ensure it does not regress and become ineffective once again.

What Is Lean Six Sigma?

Lean Six Sigma is a team-focused managerial approach that seeks to improve performance by eliminating waste and defects while boosting the standardization of work. It combines Six Sigma methods and tools and the lean manufacturing/ lean enterprise  philosophy, striving to reduce the waste of physical resources, time, effort, and talent while assuring quality in production and organizational processes. Any use of resources that does not create  value  for the end customer is considered a waste and should be eliminated.

Six Sigma Certification and Belt Rankings

Individuals can obtain Six Sigma certification to attest to their understanding of the process and their skills in implementing it. These certifications are awarded through a belt system similar to karate training. The belt levels are:

• White belt : Individuals with a white belt have received some instruction in the basics of Six Sigma, but have not yet gone through any formal training or certification program. This gives them enough knowledge to become team members.
• Yellow belt : This level can be attained after several training sessions, and equips participants with the knowledge to lead small projects and assist managers who hold more advanced belts.
• Green belt : To achieve this level, individuals take a more comprehensive course that prepares them to become project leaders.
• Black belt : After reaching the green belt level, participants can move on to black belt certification, preparing them for leadership roles in larger and more complex projects.

People with black belts can become masters and champions. Someone with a master black belt is considered an expert and strong leader with excellent problem-solving skills. A champion is a lean Six Sigma leader trained in maximizing profits through the elimination of waste and defects.

These certifications, and the courses required to obtain them, are offered by a variety of companies and educational institutions and can differ from one to another.

Real-World Examples of Six Sigma

Six Sigma is used by many companies, local governments, and other institutions. Here are two examples of how Six Sigma improved operational efficiency, saved money, and increased customer satisfaction.

Microsoft (MSFT) is one of the largest software producers in the world. It used Six Sigma to help eradicate defects in its systems and data centers and systematically reduce IT infrastructure failures.

The company first established standards for all of its hardware and software to create a baseline measurement for detecting defects. It then used root-cause analysis, including collecting data from past high-priority incidents, server failures, and recommendations from product group members and customers, to pinpoint potential problem areas.

Large amounts of data were collected on a daily and weekly basis from various servers. The incidents were prioritized based on how severely the defects affected the business and the company's underlying services. Data analysis and reporting identified the specific defects, after which remediation steps for each defect were established.

As a result of Six Sigma, Microsoft says it improved the availability of its servers, boosted productivity, and increased customer satisfaction.

Ventura County, California, Government

Ventura County, California, credited the use of Lean Six Sigma for a savings of $33 million. The county government began to use the program in 2008 and has trained more than 5,000 employees in the methodology. The county says the savings are due in part to the introduction of more efficient new systems and the elimination of unnecessary, but time-consuming, steps from its prior processes.

For example, the VC Star newspaper reported in 2019 that the county saved "$51,000 with an appointments system that reduced labor costs and rates for maintenance of county vehicles [and] almost $400,000 annually by implementing a new system to track employee leaves of absence."

How Can You Get Six Sigma Certification?

You can receive Six Sigma certification through private companies, associations, and some colleges. Keep in mind, though, that there is no single governing body that standardizes the curriculum. This means that courses can vary based on where you take them.

Can You Get Six Sigma Certification Online?

Yes, many of the universities and organizations that offer Six Sigma certification have both classroom and online offerings.

What Is the Basic Difference Between Six Sigma and Lean Six Sigma?

Lean Six Sigma uses the Six Sigma methodology (define, measure, analyze, improve, control) with the specific goal of eliminating waste in a company's, or other organization's, processes or use or materials—that is, making it "leaner." It derives in part from the principles of lean manufacturing.

Six Sigma has become a widely used quality-improvement methodology in both the private and public sectors. Anyone who wishes to learn it can take courses that lead to various levels of certification.

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Lean Thinking and Methods - Six Sigma

• Introduction

Method and Implementation Approach

Implications for environmental performance, useful resources.

Six Sigma consists of a set of statistical methods for systemically analyzing processes to reduce process variation, which are sometimes used to support and guide organizational continual improvement activities. Six Sigma's toolbox of statistical process control and analytical techniques are being used by some companies to assess process quality and waste areas to which other lean methods can be applied as solutions. Six Sigma is also being used to further drive productivity and quality improvements in lean operations.

Six Sigma was developed by Motorola in the 1990s, drawing on well-established statistical quality control techniques and data analysis methods. The term  sigma  is a Greek alphabet letter (σ) used to describe variability. A sigma quality level serves as an indicator of how often defects are likely to occur in processes, parts, or products. A Six Sigma quality level equates to approximately 3.4 defects per million opportunities, representing high quality and minimal process variability.

It is important to note that not all companies using Six Sigma methods are implementing lean manufacturing systems or using other lean methods. Six Sigma has evolved among some companies to include methods for implementing and maintaining performance of process improvements. The statistical tools of Six Sigma system are designed to help an organization correctly diagnose the root causes of performance gaps and variability, and apply the most appropriate tools and solutions in addressing those gaps.

A sequence of steps called the Six Sigma DMAIC (Define, Measure, Analyze, Improve, and Control) is typically used to guide implementation of Six Sigma statistical tools and to identify process wastes and weaknesses. Six Sigma DMAIC phases include:

• Define.  This phase focuses on defining the project improvement activity goals and identifying the issues that need to be addressed to achieve a higher sigma level.
• Measure.  In this phase, the aim is to gather information about the targeted process. Metrics are established and used to obtain baseline data on process performance and to help identify problem areas.
• Analyze.  This phase is concerned with identifying the root cause(s) of quality problems, and confirming those causes using appropriate statistical tools.
• Improve.  Here, implementation of creative solutions - ways to do things better, cheaper, and/or faster - that address the problems identified during the analysis phase takes place. Often, other lean methods such as cellular manufacturing, 5S, mistake-proofing, and total productive maintenance are identified as potential solutions. Statistical methods are again used to assess improvement.
• Control.  This phase involves institutionalization of the improved system by modifying policies, procedures, and other management systems. Process performance results are again periodically monitored to ensure productivity improvements are sustained.

Some organizations have opted to integrate their kaizen (or rapid continual improvement) processes with Six Sigma approaches. This typically results in the use of statistical tools to aid the identification and measurement of improvement opportunities during and following kaizen event implementation.

It should be noted that some lean experts believe that Six Sigma, as implemented in some organizations, can be contradictory to lean principles. In such cases, Six Sigma experts, often known as "black belts", lead improvement efforts without actively involving workers affected by the improvement effort. Lean experts typically contend that employee involvement and empowerment is critical to fostering the continual improvement, waste elimination culture that is a foundation of lean thinking.

It should be noted that Six Sigma techniques can be relatively sophisticated, and are most frequently utilized by larger organizations and organizations willing to devote resources and talent for developing Six Sigma statistical capabilities.

Several examples of Six Sigma statistical tools are described below.

• Capability Analysis.  This tool assists in the maintenance of suitable product specifications. Using this statistical model and analyzing a frequency histogram of an observed production data sample, the long run defects per million opportunities can be determined. Such analyses can consider both "short-term" variability that determines the absolute best a process can produce, and a "long-term" variability that assesses how well a process responds to customer needs.
• Gauge Repeatability & Reproducibility Studies.  These studies quantify measurement error by assessing whether measurement processes and equipment produced consistent and accurate measurement outcomes. Without such studies, satisfactory parts might be rejected and unsatisfactory parts accepted. Such errors can lead to lost sales and unnecessary waste.
• Control Charts.  Control charts are often used to ensure that essential product characteristics remain constant over time, and to help identify when problems exist. Periodic sample measurements are plotted against the mean and range to see if any noticeable process shifts or other unusual events had occurred. When characteristics cannot be measured, charts are based on the proportion of defective items in a lot.  CuSum  (Cumulative Sum of Measurements)  Charts  can also be used to monitor the cumulative sum of deviations against a target value.
• Accelerated Life Tests.  Statistical techniques such as a Weibull Distribution and Arrhenius Plot are used to estimate the failure time distribution of products, and to test products designed to last for long periods of time. Such tests are often essential when testing must be conducted under aggressive time constraints, and must engage "stress test environments" such as high temperature, thermal cycling, or high humidity, to evaluate product life.
• Variance Components Analysis.  Isolating product variability problems is particularly critical to quality assurance. With this technique, different sources of variability are isolated to help assess where variations in product quality are occurring. Such analyses also provide insight into the sources of variability for process improvement efforts.
• Pareto Analysis.  By weighting each type of defect according to severity, cost of repair, and other factors, Pareto charts are used to determine which types of defects occur most frequently. This information facilitates prioritization of response actions. Fundamental to the Pareto principle is the notion that most quality problems are created by a "vital few" processes, and that only a small portion of quality problems result from a "trivial many" processes.
• fewer defects decreases the number of products that must be scrapped;
• fewer defects also means that the raw materials, energy, and resulting waste associated with the scrap are eliminated;
• fewer defects decreases the amount of energy, raw material, and wastes that are used or generated to fix defective products that can be re-worked.

Breyfogle, Forrest W. III.  Implementing Six Sigma: Smarter Solutions Using Statistical Methods  (New York: John Wiley & Sons, 1999).

Winiarz, Marek L., James Fang and Howard Fuller.  Six Sigma Programs Yield Dramatic Improvement Through Application of Lean Manufacturing Methods in the Printed Circuit Board Industry.  SAE Technical Paper Series (Warrendale, PA: SAE International, 2001).

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6 Key Benefits of Quality Management Systems | QMS Guide

August 6th, 2024

A QMS is a formalized system that documents processes, procedures, and responsibilities for achieving quality policies and objectives.

It helps coordinate and direct an organization’s activities to meet customer and regulatory requirements and improve its effectiveness and efficiency on a continuous basis.

Key Highlights

• Enhanced operational efficiency and cost reduction
• Improved customer satisfaction and retention rates
• Ensured regulatory compliance and risk mitigation
• Fostered culture of continuous improvement
• Boosted overall business performance and profitability
• Streamlined processes for ISO 9001 certification
• Facilitated data-driven decision-making across organization

Introduction to Quality Management Systems

A robust QMS is not just a nice-to-have; it’s a critical tool for organizations striving for excellence and sustainable growth.

Key components of a QMS

QMS comprises several key components.

These include quality policies and objectives, a quality manual, documented procedures, work instructions, and records.

The system also encompasses quality planning, quality assurance , quality control, and quality improvement mechanisms.

These components work in tandem to create a comprehensive framework that guides an organization towards achieving its quality goals.

Enhancing Operational Excellence with Benefits of a Quality Management System (QMS)

QMS can revolutionize operational efficiency.

It drives process improvement , increases efficiency, and reduces costs through waste elimination.

Process improvement and standardization

One of the primary benefits of a quality management system is its focus on process improvement and standardization .

QMS implementation leads to the identification and elimination of inefficiencies in business processes.

By documenting and standardizing procedures, organizations can ensure consistency in their operations, reduce variability, and minimize the likelihood of errors.

Increased operational efficiency with the Benefits of a Quality Management System (QMS)

A well-implemented QMS significantly boosts operational efficiency.

It provides a structured approach to identifying bottlenecks , streamlining workflows, and optimizing resource allocation.

QMS tools like statistical process control and business process charting can lead to substantial improvements in cycle times and overall productivity.

Cost reduction through waste elimination

Another crucial benefit of a QMS is its ability to drive cost reduction through waste elimination.

By applying Six Sigma methodologies within the QMS framework, organizations can identify and eliminate various forms of waste – be it overproduction, unnecessary inventory, or excessive motion in manufacturing processes.

This not only reduces operational costs but also enhances the organization’s bottom line.

Driving Customer Satisfaction and Retention

Customer satisfaction is the lifeblood of any successful business, and a QMS plays a crucial role in achieving it.

QMS ensures consistent quality, meets customer expectations, and improves communication channels.

Consistent product quality with the Benefits of a Quality Management System (QMS)

A QMS plays a pivotal role in ensuring consistent product quality. Through my work with companies like Motorola and HP, QMS can significantly reduce product defects and variations.

This consistency not only meets but often exceeds customer expectations, leading to increased satisfaction and loyalty.

Meeting customer expectations

By focusing on customer requirements and feedback, a QMS helps organizations align their processes and outputs with customer expectations.

The voice of the customer becomes an integral part of the quality management process , ensuring that products and services are designed and delivered to meet specific customer needs.

Improved customer communication and feedback

A QMS also facilitates better communication with customers. It provides structured mechanisms for gathering, analyzing, and acting on customer feedback.

This continuous loop of communication and improvement not only enhances customer satisfaction but also builds long-term relationships, leading to higher customer retention rates .

Ensuring Compliance and Risk Management

Compliance and risk management are more critical than ever.

QMS helps meet regulatory requirements, facilitates ISO 9001 certification, and mitigates risks effectively.

Meeting regulatory requirements

QMS is invaluable for ensuring compliance. Through my experience working with government institutions like NATA and the US Army.

QMS can help organizations navigate and meet various regulatory requirements efficiently.

ISO 9001 certification benefits

Achieving ISO 9001 certification is often a key goal for many organizations implementing a QMS.

The benefits of this certification are numerous – from increased credibility in the market to improved operational efficiency.

Moreover, the process of obtaining and maintaining ISO 9001 certification itself drives continuous improvement within the organization .

Effective risk assessment and mitigation with the Benefits of a Quality Management System (QMS)

A QMS provides a framework for systematic risk assessment and mitigation.

Through tools like Failure Mode and Effects Analysis (FMEA) and risk matrices, organizations can proactively identify potential issues and develop strategies to address them before they become problematic.

Fostering a Culture of Continuous Improvement

A QMS is not just about processes; it’s about people and culture.

QMS fosters employee engagement, promotes data-driven decision-making, and implements effective CAPA strategies .

Employee engagement and training

A successful QMS relies heavily on employee engagement.

This not only improves the effectiveness of the QMS but also boosts employee morale and productivity.

Data-driven decision-making

One of the core principles of a QMS is the emphasis on data-driven decision-making.

By using statistical tools and methodologies, organizations can make more informed decisions based on concrete evidence rather than gut feeling or assumption.

This approach leads to more effective problem-solving and process improvement .

CAPA implementation as Benefits of a Quality Management System (QMS)

Corrective and Preventive Action (CAPA) is a crucial component of any QMS.

It provides a structured approach to addressing non-conformities and preventing their recurrence.

CAPA implementation can lead to significant improvements in product quality and process efficiency .

Boosting Business Performance with the Benefits of a Quality Management System (QMS)

The ultimate goal of any business initiative is to improve overall performance, and a QMS delivers on this front.

QMS increases productivity and profitability, provides a competitive edge, and opens doors to new market opportunities.

Increased productivity and profitability

The culmination of all the benefits mentioned above – improved processes, reduced waste, higher quality, and better customer satisfaction – inevitably leads to increased productivity and profitability.

Organizations with a well-implemented QMS often see substantial improvements in their financial performance.

Competitive advantage in the market

QMS can provide a significant edge. It demonstrates an organization’s commitment to quality and customer satisfaction, which can be a key differentiator in the market.

Opportunities for market expansion with the Benefits of a Quality Management System (QMS)

A QMS can also open doors for market expansion. Many organizations, especially in highly regulated industries, require their suppliers to have certified quality management systems .

By implementing a QMS and achieving certifications like ISO 9001 , organizations can qualify for new business opportunities and expand into new markets.

Implementing a Successful QMS

Implementing a QMS is a journey that requires careful planning and execution.

These are the key steps, common challenges, and essential metrics for measuring QMS effectiveness.

Key steps in QMS implementation

Implementing a QMS is a significant undertaking that requires careful planning and execution.

Key steps include gaining management commitment, defining the scope of the QMS, documenting processes, training employees, conducting internal audits, and continually reviewing and improving the system.

Overcoming common challenges with the Benefits of a Quality Management System (QMS)

Common challenges in QMS implementation include resistance to change, lack of resources, and difficulty in maintaining momentum.

Overcoming these challenges requires strong leadership, effective communication, and a clear demonstration of the benefits of a Quality Management System (QMS) to all stakeholders.

Measuring QMS effectiveness through performance metrics

To ensure the continued success of a QMS, it’s crucial to establish and monitor key performance indicators (KPIs).

These might include metrics related to product quality, customer satisfaction, process efficiency , and financial performance.

Regular review of these metrics allows organizations to gauge the effectiveness of their QMS and identify areas for improvement.

The Long-Term Impact of Quality Management Systems

In conclusion, the benefits of a quality management system are far-reaching and impactful.

From improved operational efficiency and customer satisfaction to enhanced compliance and risk management , a well-implemented QMS can transform an organization’s performance across multiple dimensions.

Future trends in quality management

Looking ahead, we can expect to see quality management systems evolving to incorporate emerging technologies like artificial intelligence and machine learning.

These advancements will likely lead to even more sophisticated data analysis capabilities and predictive quality management approaches.

Organizations to embrace the Benefits of a Quality Management System (QMS)

Given the numerous benefits of a Quality Management System (QMS) and the critical role that quality plays in today, organizations of all sizes and across all industries should embrace quality management systems .

A robust QMS is a strategic decision that will pay dividends in the long run.

Remember, in the world of business, quality isn’t just about meeting standards – it’s about exceeding expectations and driving continuous improvement .

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Home > Learn More About Six Sigma Black Belt > Enhance Your Career with Lean Six Sigma Black Belt Training

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In today’s competitive job marketplace, w e are all looking for opportunities to advance our careers. Isn’t it? If you are one of those aspirants, you can achieve this by completing a Lean Six Sigma Black Belt Certification. This will enhance your skill sets and will open doors to bigger roles.

Further, the certification has the potential to increase your earnings. It will also open the doors for many other opportunities. By reading this article, you will understand the advantages of the Certification and how it can potentially change your career.

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  The Technique

How to improve organizational performance by minimizing waste and optimizing systems? The answer to this is by using the technique called Lean Six Sigma. It blends the Lean principles with Six Sigma to improve organizational efficiency. Lean, as a tool of this method, trashes any activity or process that does not add worth to the service or product. On the other hand, Six Sigma works on eradicating defects and variations related to operations. Further, a certification in this area showcases your proficiency in improving the operational efficiency of organizational processes. Hence, having one as you progress in your career becomes important.

You can earn different levels of certifications, which are indicated by ‘belts’. The first level of this certification is the White Belt. The next levels are Yellow, Green, Black, and Master Black.

The Black Belt                                                 

A Black Belt is someone who has completed the certification and possesses a high level of expertise in this methodology. Within their organizations, these Black Belts are leaders and change agents. They also have a deep understanding of the technical and strategic aspects of this concept. This enables them to deliver significant results and design impactful improvements.

Responsibilities

• Manage projects
• Train team members
• Drive continuous improvement initiatives.

Benefits of Certification

• One of the main benefits of the course is that your problem-solving ability will improve considerably. After the completion of the course, the way you look at things will completely change. You will also learn to identify and analyze the root cause of a problem and implement the right solutions. As a result, you will be able to handle complex environments and also improve the processes in your organization.
• Secondly, the Black Belt Certification is such an important qualification that it is highly sought after by people working in the manufacturing, services and finance sectors. After this certification course, you will become a valuable resource for your organization. Hence, you will be able to demand a higher salary compared to your non-certified counterparts.
• The training will also focus on project management and leadership skills. In addition, the certification will help you gain valuable insights into leading teams and driving organizational changes. Furthermore, it will help you transition to leadership roles.
• The certification teaches you to make data-driven decisions. Such an analytical decision-making process leads to better and more efficient outcomes for the organization.
• Lastly, the Black Belt certification provides formal recognition of your expertise and commitment to continuous improvement. As it showcases your expertise in leading significant process improvement initiatives for employers and clients, your credibility and professional reputation increase considerably. 

Prerequisites

The Lean Sigma Black Belt Certification is a higher-order certification. Therefore, most certifying bodies ask for a few prerequisites to be fulfilled. Some of these pre-requisites that would help you include:

i) Experience: Depending on the certifying agency, you may need to have professional experience in Process Improvements and managerial roles. Some of these agencies may even specify the minimum number of years of experience as it is the responsibility of a Black Belt to lead teams and manage complex projects.

ii) Green Belt: There is a demand and pre-requirement from the industry for the Lean Six Sigma Green Belt certification. Hence, most agencies require you to complete the Green Belt before you venture into the Black Belt. So, now that you already have a Green Belt certification, you will have a strong foundation. This will enhance your understanding of the subject better.

iii) Education: A bachelor’s degree in engineering or any related field is preferred, if you wish to get a Black Belt certification. However, relevant work experience can replace educational qualifications. 

Syllabus of Training

This certification curriculum includes both theoretical and practical modules. It covers topics such as

• Firstly, Lean Principles: Understanding waste reduction, value stream mapping, and continuous flow.
• Six Sigma Tools: Mastering DMAIC methodology, statistical analysis, and process mapping.
• Project Management: Learning to manage projects, lead teams and drive change.
• Problem-Solving Techniques: Becoming an expert in root cause analysis, hypothesis testing and regression analysis.
• And finally, practical applications: Complete a project that shows your ability to apply the Lean Six Sigma theoretical concepts to real-world problems.  

 Certification Exam

This Black Belt exam tests your knowledge of the Lean Six Sigma principles and your ability to apply them effectively. You will also come across several recognized certifying organizations, which offer certification for the exam.

To prepare for such a certification exam, it is a good idea to enroll in a training program such as the Henry Harvin Lean Six Sigma Black Belt Training & Certification course.

The formal training by Henry Harvin for this program offers advantages such as

• Learning in a structured way
• Gaining access to material you are likely to be tested on in a certification exam.

Further, as a testament to your expertise and dedication you will receive the Lean Six Sigma Black Belt Certification on successfully passing the exam.

Salient Features of the Henry Harvin Course

•       Three certifications from IASSC Henry Harvin and NSDC
•       Learn from Industry Experts with relevant experience
•       Project Completion Letter Learn with Projects and Practical Training
•       Access to 5+ Soft Skills courses
•       Placement opportunities with 350+ Corporate Partners
•       Attend Unlimited Batches with different Industry Experts for the next 1 year              without paying anything extra

  Benefits

1. industry recognition.

Lean Six Sigma Black Belt Certification is recognized globally in most of the sectors. This certification i s also p roof of your understanding and involvement in various areas like manufacturing, healthcare, and financial services to name a few which you develop as part of process improvement or quality management topics. No wonder, it sets people who complete the certification apart from their peers and also positions them as a leader in their respective fields.

2. Leadership

Next, you can take on leadership roles in an organization once you complete the certification. You also get the skills to run projects, lead teams, and drive strategic programs that open up the doors for Director of Operations, Quality Director and Chief Operating Officer positions.

3. Networking and Professional Growth

In addition, you can connect with experts in the respective field by completing your Lean Six Sigma Black Belt certification. It is also the gateway to joining a community of individuals dedicated to continuous Improvement and Excellence in Quality. Thus, this networking will provide valuable insights, support, and opportunities for professional growth.

4. Personal Satisfaction

Finally, the Lean Six Sigma Black Belt certification will bring great personal satisfaction. It also increases confidence and knowledge towards the handling of complex problems and allows one to make a difference in the organization.

The Lean Six Sigma Black Belt training is a transformative experience that will take you to the next level. Besides, you can position yourself as a valuable asset in any industry with these advanced problem-solving techniques and better leadership skills.

In addition , pursuing this training opens up a personal growth opportunity. Hence, opting for Black Belt training is a wise decision that will pay rich dividends throughout your career. Whether your goal is to grow in your present role or pursue future opportunities, this certification is a powerful tool to achieve your objectives.

Recommended Reads

Walmart Case Study: Lean Six Sigma Implementation in 2024

5S Lean Management & Six Sigma in 2024

10 Six Sigma Tools you Need to Perform Better in your Career: 2024

Top 30 Six Sigma Interview Questions and Answers in 2024

7 Benefits of Six Sigma in Biotechnology in 2024 

1. How will a Sigma certification help in developing your career?

A certification can help you develop professional skills. Also, some of the skills include problem-solving and critical thinking skills.

2. Expand DMAIC .

This methodology comprises five phases namely, DMAIC – Define Measure Analyze Improve and finally Control

3. How do I get a Black Belt certification?

You can enroll in various training courses being offered by reputed institutes like Henry Harvin to complete your Black Belt Certification. You could also use self-study and then write the exam

4. What is the validity of a Black Belt?

You have to renew the certification every three years.

5. What are the career prospects of a Black Belt?

The certification improves your chances while job hunting. It will also help you end up in jobs such as that of Project Managers, Directors of Operation, Quality Director etc.

Henry Harvin Ranks #1 Six Sigma Certification Course Amongst Top 5 by Business Standard

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