Six Sigma

A quality standard of only 3.4 defects per million opportunities; 99.9996% good. 

Six Sigma methodologies focus on mathematical and statistical tools to improve the quality of processes that have already been mastered. Its application follows a five-step process: define, measure, analyze, improve and control (Define, Measure, Analyze, Improve, Control). This process is also often referred to as DMAIC. 

Motorola coined the Six Sigma technique in 1986 as a way to achieve the company's improvement goals in manufacturing and support operations. The term refers to the number of standard deviations a point is away from the center point in a bell curve. 

Many Lean thinkers apply Six Sigma techniques to solve intractable quality problems in value-adding processes that have already been mastered and where non-value-adding processes have been eliminated through total value stream analysis. 

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