Control or Verify Phase
If the project involves an improvement to existing systems, the term “control” is used to refer to the final six sigma project phase in which tentative recommendations are confirmed and institutionalized. This follows because inspection controls are being put in place to confirm that the changes do initially increase quality and that they continue to do so. If the associated project involves new product or service design, this phase also involves confirmation. Since there is less emphasis on evaluating a process on an on-going basis, the term “verify” refers evaluation on a one-time, off-line basis.