What is Lean Six Sigma?

Lean Six Sigma in simplest terms is a methodology to improve business processes from the scale of an entire organization to the scale of an individual process. It is a methodology with a defined structure, roadmap, and tools to discover the root causes of process problems.

Lean Six Sigma is a combination of two powerful methodologies: LEAN and Six Sigma. Let’s break down these two methodologies:

What is LEAN?

  • LEAN leverages the understanding of what steps in the process add value to the customer and maximizing that value by reducing the steps that do not add value (otherwise known as “waste’)
what is lean; LEAN Principles
LEAN Principles

What is the goal of LEAN?

  • The goal of LEAN is to reduce waste in the process. By reducing waste in the process, you will reduce the number of tasks occurring in the process. This reduction of wasteful steps will gain the organization:
    • Capacity to do more customer-value-added tasks,
    • Reduced operating costs, and 3)
    • Provide better quality through fewer defects (because the product or service is handled less).

What is Six Sigma?

  • Six Sigma is a data-driven approach to reducing defects in a process.
  • In the Six Sigma methodology, it is believed that variation plays a significant role in the creation of defects.
  • Six Sigma uses the DMAIC methodology to find and reduce variation in the process by focusing on the key process input variables (or KPIVs).
    • These KPIVs are potentially the 20% of the process that causes 80% of the “pain”.
what is six sigma
What is six sigma; Six Sigma DMAIC

What is the goal of Six Sigma?

  • The goal of Six Sigma is to reduce defects to reach the performance target defined by the customer.
    • To constantly strive for a Six Sigma performance (less than or equal to 3.4 DPMO Defects Per Million Opportunities).
      • Most organizations will never meet this goal, so they set SMART (Specific, Measurable, Attainable, Relevant, and Time-bound) goals in between Six Sigma (which is the perfect state) and their current baseline.
      • The SMART goals are called KPIs (Key Performance Indicators)
      • These KPIs are updated once the organization can meet them comfortably, keeping the organization on the path of “continuous improvement”.

What is the Synergy between LEAN and Six Sigma?

I like to think of Lean Six Sigma as the human brain. There are two hemispheres that make up the brain (the right and the left hemisphere).

What is lean six sigma; What is the Synergy between LEAN and Six Sigma?
What is the Synergy between LEAN and Six Sigma?
  • The LEAN side of the brain: The left hemisphere is the more artistic, tactile, and creative side of the brain. We relate this side to LEAN. In the LEAN methodology, we use visual data like TAKT Time and ANDON boards, KANBANS, 5S, and other visual management tools. LEAN wants the operator to constantly add value to the process by having all the necessary information surrounding them and visuals rather than wasting time looking for the information.
  • The Six Sigma side of the brain: The right hemisphere of the brain is the more academic and logical side of the brain. We relate to this side of Six Sigma. In the Six Sigma methodology, we use quantitative data to understand our capability to meet the target specification of the customer (rather than a Go/NoGo gauge to react only when we are outside of specifications). We use root cause analysis tools that prove statistically significant effects through hypothesis testing rather than using opinions of the root cause. We use tools like SPC Charts and Capability Charts to control the process at the process owners’ level (rather than only managing the process at the “ivory tower” level).
  • The synergy between LEAN and Six Sigma: Can a complex process that is full of waste cause variation in the Y (or output)? I hope you replied with a resounding “YES!”. As we remove waste (and consequently steps) from the process, the potential for variation decreases. As we reduce waste, can we gauge the effect on the process by tracking the standard deviation (or the measurement of variation)?
    • Can you track TAKT time on a Control Chart to see trends and abnormal variation? Can you track TAKT Time with a capability chart to gauge how well the process meets target TAKT? Six Sigma uses VISUAL tools populated through data to understand the nature of VARIATION in the process.

Just like the brain, LEAN and Six Sigma are interconnected, thus we get the term Lean Six Sigma. Both methodologies work in concert to provide holistic improvement.

What is the History of Lean Six Sigma?

history of lean six sigma
History of Lean Six Sigma

“Certified in Lean Six Sigma can be traced to Motorola in the United States in 1986. Six Sigma was developed within Motorola to compete with the Kaizen (or lean manufacturing) business model in Japan. As a result of Six Sigma, Motorola received the Malcolm Baldridge National Quality Award in 1988.

In the 1990s Allied Signal hired Larry Bossidy and introduced Six Sigma in heavy manufacturing. A few years later, General Electric’s Jack Welch consulted Bossidy and began Six Sigma at General Electric. At this point, Six Sigma became more widely accepted and known in the manufacturing world.

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

The first concept of Lean Six Sigma was created in 2001 by a book titled Leaning into Six Sigma: The Path to Integration of Lean Enterprise and Six Sigma by Barbara Wheat, Chuck Mills, and Mike Carnell. The book was developed as a guide for managers of manufacturing plants on how to combine lean manufacturing and Six Sigma to dramatically improve quality and cycle time in the plant. Wheat, Mills, and Carnell narrate the story of a company that was skeptical about implementing Lean Six Sigma, but because of doing so was able to successfully improve the quality and efficiency in all aspects of a business.

In the early 2000s Six Sigma principles expanded into other sectors of the economy, such as Healthcare, Finance, Supply Chain, etc.”


What are the Primary Roles of Lean Six Sigma?

lean six sigma roles

What are the Primary Roles of Certified Lean Six Sigma professionals?
  • The Lean Six Sigma White Belt: The certified Lean Six Sigma White Belt understands the structure and the goals of Lean Six Sigma. Everyone within the Lean Six Sigma implementation should be trained as a White Belt. They are also the Subject Matter Experts (or process owners) in a project working with the change agents to improve the process.
  • The Lean Six Sigma Yellow Belt: The Lean Six Sigma Yellow Belt is a step up from the Lean Six Sigma White Belt. They understand basic root cause analysis tools and lead small-scale projects within their functional areas.
  • The Lean Six Sigma Green Belt: The certified Lean Six Sigma Green Belt is a cross-functional change agent that focuses 25% of its time on Lean Six Sigma projects. They are trained on statistical techniques that prove/disprove statistically significant effects of the X (or Xs) on the Y (or Ys).
  • The Lean Six Sigma Black Belt: The Lean Six Sigma Black Belt is an advanced change agent who has spent several years and gained project experience as a Green Belt. They are trained in advanced statistical techniques including the Design of Experiments, advanced regression, how to evaluate non-normal data, and advanced Lean Techniques. The black belt is focused on Lean Six Sigma projects 100% of the time.
  • The Lean Six Sigma Master Black Belt: The Certified Lean Six Sigma Master Black Belt is a teacher and mentor for all other belts. To fulfill this role, the MBB must have significant project experience (10 or more years) to relate the complex methodologies of LEAN and Six Sigma to the students. They also work with the leaders of the organization to manage the Lean Six Sigma implementation and culture change.
  • The Lean Six Sigma Champion: The Lean Six Sigma Champions are the leaders and decision-makers of the company who drive the Lean Six Sigma continuous improvement initiative. They remove barriers for the Lean Six Sigma project team. The champions are the “cheerleaders” of the Lean Six Sigma continuous improvement efforts to change the culture.

What are the benefits of Lean Six Sigma?

benefits of lean six sigma
What are the benefits of being certified in Lean Six Sigma?

Being Certified in Lean Six Sigma provides numerous benefits for organizations. It not only saves money but also changes the attitude of employees and the functionality of the organization. Through the implementation of Lean Six Sigma, organizations can expect the following beneficial outcomes:

  • Increase in Profit: As a result of eliminating waste and improving the quality of production, Lean Six Sigma reduces costs for organizations and increases profitability. General Electric experienced profit-cost savings exceeding $2 billion.
  • Standardized and Simplified Processes: With the help of value stream mapping, Lean Six Sigma eliminates waste in processes and unnecessary steps to streamline production. The processes are simplified so that they are easier to follow and less likely to lead to error. The simplified processes will also reduce time, leading to a decrease in overhead costs.
  • Decrease in errors: With the simplification in processes steps and a detailed investigation into the main causes of error and waste in the organization, Lean Six Sigma drastically reduces errors such as defects and miscalculations
  • Employee Performance/Development: Lean Six Sigma stresses the importance of the ideas and observances of individual employees to the overall success of an organization. With Lean Six Sigma, the feeling of self-importance and significance increases among employees and leads to an increase in motivation and better job performance.
  • Value to Customer: Lean Six Sigma allows companies to improve their processes and the quality of their products. In turn, they can produce more products at a cheaper price with less error. Customer satisfaction will increase, which will then lead to an increase in customer loyalty.

What are the benefits of Lean Six Sigma to you and your career?

What are the benefits of being certified in lean six sigma?
What are the benefits of being certified in lean six sigma?

Certified Lean Six Sigma practitioners are in high demand in all industries across the globe. The Lean Six Sigma methodology is applicable in manufacturing, finance, government, healthcare, retail, insurance, IT, and more. Some of the benefits a Lean Six Signa practitioner brings to the organization are:

  • An ability to drive process thinking to identify and fix opportunities
  • The capability to define critical performance measures and improve overall performance
  • Learn how to measure and improve core business KPIs
  • Develop your project management skills to drive high-performing teams
  • Develop your ability to manage and engage senior Stakeholders
  • Learn and become familiar with core change management skills
  • Deepen your business understanding and insights
  • Improve your career transition and gain an edge over other candidates
  • Making data-driven decisions in your everyday activities
  • It will change the way you work forever

Article: 5 Benefits of Lean Six Sigma Certification (https://www.leanscape.io/what-are-the-benefits-of-lean-six-sigma-training/)

These skills are highly sought after in leadership positions. Being certified in Lean Six Sigma will give you an advantage over the competition. It is a powerful credential to add to your resume.

How do I explain Lean Six Sigma simply?

In our Lean Sigma certified courses, we teach the concept of the Sigma Value with a story that helps our students easily understand the concept.

We tell the class a story of a college football coach that is evaluating five kickers as field goal kickers for an upcoming game. The coach has one hundred footballs, each with an RFID attached. He has a GPS solution that tells him exactly where the football crosses the field goal (whether inside or outside of the goal). He gives his kickers a chance to kick each of the one hundred footballs through the field goal from the center of the field 35 yards back from the goal.

explaining six sigma with a example using five field goal kickers

His first four kickers take their turns. Each kicker kicks all one hundred footballs between the uprights, and not one ball misses the goal. Although, all four kickers were “all over the goal,” some kicks were high, some low, some near the right goal post, and others near the left goal post. The footballs never consistently crossed the goalpost at the same point.

The 1st four kickers performance

Would you say that the first four kickers are “good”? In our classes, most agree that the first four kickers are indeed “good” kickers because they did not miss the goal in a sample of 100 kicks. Although, if you said “Yes”, you would be wrong.

The fifth kicker also kicks all one hundred footballs through the uprights but he consistently “splits” the uprights. His kicks are tightly grouped in the center of the field goal with slight variation between kicks.

The fifth kickers performance

We then ask the class, “Who are you going to choose to be the field goal kicker during the game?” Most choose the fifth kicker. Why? Because he is more consistent. The fifth kicker will be more predictable because he and his team have learned through practice to have better control over their critical inputs. Those critical inputs could include the angle of the kicker’s head over the ball when he kicks; the kicker follow through; the foot pounds of pressure when kicking; the angle of the football placed for the kick; etc. All these inputs can be measured, recorded, and improved to enhance the kickers’ performance.

If you were to film all 100 kicks that the fifth kicker made and superimpose the filmed kicks on top of each other, you would see little variation in his kicking method. This consistency leads to slight variation in his where the football crosses the plane of the goal.

Let us go back and review “why the first four kickers were not good.”

The sample of one hundred kicks gives us a glimpse (in statistics, it is called an “inference”) into the capability of the kicker to kick 1000, 10,000, or 100,000 kicks.

Sample of 100 kicks from a population of kicks

We will not know what that sample is inferring until we look at it through some sort of statistical analysis tool. To simply say the first four kickers are “Good” based on the sample being “Good” (as opposed to “Bad”) is to ignore the variation between kicks.

You might ask “How can we take variation into account when determining if the kicker is good or not”. Great question! … Let us say that each kick of the football gave us a data point (a combination of an X, Y, and Z coordinate) from a virtual grid that surrounds the field goal (they actually do this in the NFL). When we calculate the amount of variation of the sample of 100 kicks from kicker #1, we would see that there is a large standard deviation. This is where we turn that standard deviation number into a picture to show the impact variation has on the performance of the kicker to hit the target (the center of the goal). As Lean Six Sigma practitioners, we are interested in +/- 3 standard deviations from the average (Read more about why we use the +/- 3 standard deviation from the average).

Taking the sample of 100 kick into account when explaining the performance of the kicker

When we show the normal curve (which equals +/-3 standard deviations from the average) and overlay it on the field goal, we might find that the bell curve exceeds the two goalposts. This is an inference as to what the population of kicks (taken from the samples of 100 kicks of each of the four kickers) will look like in the future if they still perform with the same variation in kicks.

While the 5th kicker does not create a defect in his sample of 100 kicks, he will eventually create a defect

When we calculate the standard deviation of the fifth kicker and use it to draw the bell curve overlayed on the field goal, we see a bell curve that fits inside the two goal posts.  

The fifth kicker has a smaller standard deviation

I will ask the question that I asked earlier in this discussion: “Who are you going to choose to be the field goal kicker during the game?” 

In the Lean Six Sigma methodology, this is what we are trying to achieve. We strive to be that fifth kicker who has phenomenal control over his inputs to create a kick that splits the goalposts every time. Just like the kicker, organizations that are consistently and predictably producing good products and services will be more valuable in the eyes of customers.

Do you have an interesting story or teaching tool to explain what it is like being Certified in Lean Six Sigma? If so, include the story or tool in the comments below.

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