As we already have mentioned, the model of SPC is fundamentally that of Shewhart and Deming and is capsulated in the PDSA submodel. To have a successful SPC program, one has to understand and follow this submodel . The minimum requirements are as follows :
In the plan phase for a change, the process owner must be aware of
What changes are desirable?
What data are available?
In the do phase, the process owner must be willing to carry out the change, preferably on a small scale.
In the study phase, the process owner must be data driven by
Being willing to study the data.
Being able to answer the fundamental question, "What did we learn?"
In the act phase, the process owner must be willing to
Adopt or abandon the change
Run through it again ”with modifications if necessary