ABSTRACT
As we said in Volume 1 of this series, Six Sigma methodology is primarily a problemsolving methodology. It solves problems by the
Six Sigma breakthrough strategy
,
which is the DMAIC model. If we accept this, we must also accept the fact that, just like any other methodology for solving a problem, Six Sigma is by definition an appraisal approach, for it tries to eliminate the nonconformance after it has occurred. Consequently, Six Sigma in the form of the DMAIC model is indeed an appraisal method utilizing a systematic approach to what has been
a piecemeal
intervention of many tools and methodologies over the last 75 years or so (probability concepts, DOE, FMEA, and so on).
