“Don’t use Six Sigma to tackle special cause variation!”

is one of the common phrases being repeated by Lean Six Sigma coaches and a very important recommendation for the management, too.
The Six Sigma methodology is indeed targeting variation that is an inherent part of the process – common cause variation that has been expected and tolerated due to its unknown and supposedly complex root causes. Understanding this variation and analysing the real root causes before implementing improvements is a fundamental pillar of the methodology and driver for its success. …