What is Six Sigma

What is Six Sigma

First, what it is not. It is not a secret society, a slogan or a cliche. Six Sigma is a highly disciplined process that helps us focus on developing and delivering near-perfect products and services. Why ”Sigma“? The word is a statistical term that measures how far a given process deviates from perfection. The central idea behind Six Sigma is that if you can measure how many “defects” you have in a process, you can systematically figure out how to eliminate them and get as close to “zero defects” as possible. Six Sigma has changed the DNA of GE — it is now the way we work — in everything we do and in every product we design.

Six Sigma is a set of techniques, and tools for process improvement. It was developed by Motorola in 1986. Six Sigma seeks to improve the quality of process outputs by identifying and removing the causes of defects (errors) and minimizing variability in manufacturing and business processes. It uses a set of quality management methods, including statistical methods, and creates a special infrastructure of people within the organization ("Champions", "Black Belts", "Green Belts", "Yellow Belts", etc.) who are experts in the methods.

Each Six Sigma project carried out within an organization follows a defined sequence of steps and has quantified value targets, for example: reduce process cycle time, reduce pollution, reduce costs, increase customer satisfaction, and increase profits.

The term Six Sigma originated from terminology associated with manufacturing, specifically terms associated with statistical modeling of manufacturing processes. The maturity of a manufacturing process can be described by a sigma rating indicating its yield or the percentage of defect-free products it creates. 

A six sigma process is one in which 99.99966% of the products manufactured are statistically expected to be free of defects (3.4 defective parts/million),

Key Concepts of Six Sigma

At its core, Six Sigma revolves around a few key concepts.

Critical to Quality: Attributes most important to the customer

Defect: Failing to deliver what the customer wants

Process Capability: What your process can deliver

Variation: What the customer sees and feels

Stable Operations: Ensuring consistent, predictable processes to improve

what the customer sees and feels

Design for Six Sigma: Designing to meet customer needs and process capability