Lean Processes IV: Six Sigma

Lean Processes IV: Six Sigma

In some business circles, a debate has been going on, comparing Lean principles with Six Sigma to prove an advantage of one or the other system. While it may be more practical to choose one of the two for implementation in certain companies, the two systems can be incorporated together. Incorporating Lean principles and Six Sigma leads to even higher business efficiency and effectivity than focusing on one system exclusively.


Six Sigma

Six Sigma was first introduced in the 1980s as a set of tools geared to process improvement. The term itself comes from the rating of manufacturing process maturity which is expressed by the Greek letter sigma. Motorola, an American communications company that developed a set of six manufacturing goals registered them as Six Sigma. These core principles of Six Sigma are:

• reduction of process variation leading to stability in process results • clearly defined, measurable, analyzed, and controllable characteristics of the business processes

• a strong commitment to quality improvement shared by all levels of the given organization

• clarity of focus on measurable profit

• emphasis on quality management and leadership in the organization

• a commitment to verifiable data and methods in the decision-making process

The goal of these principles can be described in terms of increase and reduction. Any project incorporating Six Sigma principles should experience an increase in profits and customer satisfaction which reducing costs, pollution, and process cycle time.


Six Sigma Methodology

There are two Six Sigma methodologies to choose from, depending on the character of a project. For projects which are focused on the creation of a new product, service, or process design, there is a DMADV methodology. Alternatively, if a project aims at the improvement of an existing product, service, or process, then DMAIC methodology is more suitable.

The acronym DMADV stands for five words describing five consecutive phases of the development. These are:

• define

• measure

• analyze

• design

• verify

The DMAIC methodology has the following steps:

• define

• measure

• analyze

• improve

• control

As seen above, the two methodologies differ in the last two phases. Improving, rather than designing is the fourth step when it comes to an existing process. Likewise, a verification of a pilot run in case of a new project gives way to a broader, long-term, and regularly performed control of already established products, services, or processes.


Similarities and differences between Lean and Six Sigma

There are quite a few similarities between the two methodologies. For both, the value is defined by the customers through their direct experience. Data is collected to assess performance. Both approaches are widely used in different fields, far beyond the original domain of manufacturing and their implementation leads to waste and variation reduction.

On the other hand, the differences between Lean and Six Sigma are complementary. While Lean principles focus on reducing waste, Six Sigma’s focus is on variation. In both cases, the efficiency is improved. Where Six Sigma uses statistical analytical techniques, Lean relies on visual techniques. Process changes are implemented through a revised value stream map in Lean processes while Six Sigma implements changes through modification of setup procedures and measurement systems.


Lean Six Sigma and its benefits

When Six Sigma methodology combines with principles and tools of Lean, a new and enriched approach comes out. The strength of both methodologies woven together leads to increased efficiency and profitability that would not be attained had only one of the approaches been used. These are some of the following benefits of the Lean Six Sigma approach:


Process simplification

One of the most significant benefits that Lean Six Sigma brings is the simplification of the processes. This is done by identifying areas of inefficiency and waste. Once they are removed, the processes are more straight-forward and faster. Such processes lead to fewer mistakes and thus to the higher quality of both performance and result.


Error reduction

Lean Six Sigma seeks out errors with the aim of their swift removal. This is done by focusing on data and statistics which singles out the most crucial errors. Their elimination then leads to improved quality of the process and ultimate business success.


Active process control

The ability to actively control processes in the organization stems from short cycle times and focus on real-time data when it comes to the creation of control systems. Short cycles and the subsequent active control allow the operators to be directly involved in the management process. Value stream maps and control charts play a key role in understanding the processes.


Performance predictability

An actively controlled, simplified process, void of its errors is a process that is manageable and predictable in terms of cycle times, costs, and quality output. Lean Six Sigma advocates for predictability to improve performance, agility, and morale among employees. Ultimately, such an approach leads to fewer complaints and more satisfaction among customers.


Improvement of personal skills and abilities

Besides benefits influencing the organization as a whole, Lean Six Sigma likewise offers a set of personal benefits and one of them is the improved level of personal effectiveness. The Lean Six Sigma methodology offers a process of a well-designed set of analytic and problem identification and solution tools and techniques that an individual can adopt to boost his abilities, regardless of a job position and industry domain.

On top of the effectiveness, Lean Six Sigma helps individuals develop and practice their management skills. This is possible through exposure to different functions while working on a Lean Six Sigma project. A strong reliance on team member interaction leads to better communication while decision-making skills are put to practice as well.

Lastly, Lean Six Sigma methodology and practices are acquired through a set of courses, leading to different types of certification. Obtaining a Lean Six Sigma certificate opens new job opportunities and can lead to promotion within or beyond the current industry.



George, Michael L. (2002). Lean Six Sigma: Combining Six Sigma Quality with Lean Production Speed (1st ed.). McGraw-Hill Education.


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Lean Processes IV: Six Sigma