As an example, donut shop will be used to illustrate the focal point of Six Sigma key concepts.Failure of six sigma project can be attributed to lack of understanding these key concepts.
The taste of donut and choices are the attributes most important to customer, in six sigma concept. It’s called CRITICAL TO QUALITY.
Any failure to delivery what customers want are called DEFECT, yeah you are right. It does sound kind of manufacturing term. You can change it to rework or error.
PROCESS CAPABILITY is about what the processes in donut shop can deliver to its customers. This is how competitor differentiates them from each other.
VARIATION in process is something to do with how the customer sees and feels in engaging or doing business with the shop.
A less variation in process leads to a STABLE OPERATIONS which will make sure consistent and predictable customer experience for its customer.
Finally, the concepts of DESIGN FOR SIX SIGMA mean meeting customer needs and process capability by understanding Critical to Quality, defects from customer point of view and control process variations to minimize inconsistent product/service delivery.
All yellow belt or green belt candidates will be taught how to manage project with DMAIC methodologies and the lean sigma tools are designed to address all concept requirement.