The inspector who taught you something: lessons that stuck

Not every inspection memory is a horror story. Most experienced supers carry one lesson an inspector taught them — a way of testing an outlet, a place water hides, a reading of a standard they had wrong for years — that changed how they walk every unit since. Those lessons are worth more shared than kept. I'll start the thread rules: name the lesson, not the inspector, and tell us what you do differently now because of it. What did an inspector teach you that you still use on every walk? — Admin