Six Sigma is based on a handful of basic principles, and these principles create the entire Six Sigma arrangement. Here are Six Sigma’s fundamental principles:
Y=f(X) + ε: All outcomes and results (theY) are determined by inputs (theXs) with some degree of uncertainty (å).
To change or improve results (the Y), you have to focus on the inputs (theXs), modify them, and control them.
Variation is everywhere, and it degrades consistent, good performance. Your job is to find it and minimize it!
Valid measurements and data are required foundations for consistent, breakthrough improvement.
Only a critical few inputs have significant effect on the output. Concentrate on the critical few.
Every decision and conclusion has risk (ε), which must be weighed against the context of the decision.