A Six Sigma definition is closely related to statistical modeling of manufacturing processes.
The concept originated from a sigma rating, which indicates the number of defect-free products developed in a manufacturing process.
below, we will examine this definition and the Six Sigma methodology in more detail.
Six Sigma: Definition and Description
The term “Six Sigma” originated within statistical quality control an refers to manufacturing output with extremely low levels of defects – lower than 3.4 per million opportunities.
Six Sigma is a business methodology that aims to achieve these results through the application of statistical and data-driven methods.
This approach has several underlying assumptions:
- Stability and predictability in business processes is essential to organizational effectiveness
- Both manufacturing and business processes can be defined, measured, analyzed, and improved
- A commitment to statistical and data driven methods should be made by everyone within the organization
Six Sigma has two frameworks that are frequently used:
- DMAIC, a five-phase methodology aimed at improving projects
- DMADV, a five-phase method aimed at creating new product or process designs
Through methods such as these, Six Sigma aims to improve quality management and control across the organization. Although it may not be perfect, Six Sigma generally achieves positive outcomes whenever it is applied.
It is not, however, the only process and performance improvement methodology.
Six Sigma vs. Lean
Lean and Six Sigma are both designed to continuously improve processes and business outcomes. The two methods, however, differ in their approach.
The primary aim of Six Sigma, as mentioned, is to reduce defects, thereby improving quality, profits, products, processes, and customer experiences. Six Sigma, like the lean methodology, is designed to achieve certain business outcomes, such as increased financial returns and improved customer value.
Lean, however, aims at waste reduction through processes such as the build-measure-learn cycle. Namely:
- Building new products and processes
- Measuring the effectiveness of those processes
- Learning from those analyses
The cycle is then repeated continuously, with the result that business processes gradually improve and waste is gradually reduced over time.
Although the outcomes of both lean and Six Sigma may overlap to a certain extent, they do have different effects on the organization and their outcomes will also differ to a certain extent.
Choosing the Right Process Improvement Method
There is not necessarily one “correct” method for every situation. Instead, your organization should evaluate its own goals and direction, then choose a method that is most aligned with its strategy and values.
An organization that is data-driven and committed to using quantitative approaches in business may prefer the Six Sigma approach. On the other hand, an organization that wants slightly more flexibility, without the emphasis on data and statistics, may prefer the lean approach.
Or your business may choose to combine the two.
Lean Six Sigma is the approach that takes the best of each system and integrates them into one.
Characteristics of the Lean Six Sigma approach include:
- Reducing waste
- Reducing variation and defects
- Eliminating errors
- Aligning the corporate culture around the methodology
- Continuous improvement
In short, like both of the methods listed above, Lean Six Sigma attempts to maximize customer success, enhance profits, and improved continuously, while reducing defects and waste.
There are different variations on this approach. Some emphasize a more data-driven method, while others incorporate more elements from the lean methodology.
In either case, the result is often a methodology that is flexible, while able to more effectively meets the needs of an organization. Perhaps this explains why Lean Six Sigma has become so popular.
Certification in Six Sigma, Lean, and Lean Six Sigma
Given the popularity of these systems, it should be no surprise that certification programs have cropped up around the world.
There are certification programs for specialties such as:
- Six Sigma
- Lean Six Sigma
- Lean Manufacturing
- Lean Management
- Lean Product Development
Most certifications for Six Sigma and Lean Six Sigma tend to follow a ranking system similar to karate or judo belt systems.
For example:
- A green belt certification requires attending a course and learning core concepts, such as DMAIC and DMADV
- A black belt certification applies Six Sigma concepts to drive organizational change, analyze statistics, supervise green belts, and so forth
- Master black belts and champions are senior managers or business leaders who lead Six Sigma strategies across the organization
Each certification can certainly be beneficial to one’s career, though, like any other certification, it will only be valuable if it is used bye the organization.
An organization that prefers one method over the other, in other words, would value a certification in that area.
Final Thoughts
Six Sigma’s definition originated within statistics, quality control, and manufacturing.
However, it has become a popular term thanks to the Six Sigma methodology, which also began in manufacturing but has since spread to many other disciplines. The term and the Six Sigma methodology have arguably become even more popular after it was combined with the lean methodology, another very popular business process improvement methodology.
Today, understanding the statistical meaning behind the term is less important than understanding the business methodology that has become so widespread.
