A process is monitored with a control chart. The process is correctly judged to be in-control once the results from the most recent sample are plotted. Therefore, all of the output produced at that time is good.

Question

Quizplus · Accepted Answer

Just because the most recent sample falls within control limits, it does not necessarily mean all previous output was good. It is possible that there were previous batches that were out of control but were not detected or corrected. Control charts are designed to monitor and detect variations in the process, but they do not guarantee that all output produced at a certain time is defect-free.

A Process Is Monitored with a Control Chart