As an example of treatment, it is reported how the way a patient undergoing physiotherapy after leg surgery changes over time. This is the usual result that can be obtained using the Corrective and Preventive set od actions (CAPA process).
It is clear that after 3 weeks of physiotherapy the patient has regained his own way of walking. If the patient had been discharged before showing this behavior (length of steps under statistical control) he would have been discharged too early because he is still in the process of improvement, while resigning him later would mean wasting time for everyone because a system that has achieved statistical control cannot more improve.