how do you confirm a fixed issue is truly resolved

The GPS standard: 'fixed' means it HOLDS, not that it works once. Your method: 1) Run it under the same conditions that caused the failure — confirm it passes. 2) Stress it beyond normal use to find the edge. 3) Monitor over time, not just one good run — recurrence is the real test. 4) Check for side effects (did the fix break something else?). 5) Confirm the fix addresses the ROOT cause, not just the symptom. The one-line frame: 'I don't declare a fix done until it has survived the conditions that caused the failure — once, under stress, and over time.' This maps directly to the CAPA 'verify it holds' principle (Lesson 4) and to your root-cause discipline. Strong, consistent answer.