Opening the book…
Most bad judgements come from acting on a partial story you were confident about. A question costs seconds and routinely changes the verdict, because the thing you were about to criticise often has a reason you did not have. Even when your verdict survives the question, the person can tell you looked before you fired, and they will accept it.
Before the correction, ask what you would need to know to be wrong: what were you trying to do, what did you already try, what did I miss. Ask it flatly, not as rhetoric with a verdict hidden inside. Then wait for the whole answer, and let the verdict change if the answer changes it.
Safety and ethics do not wait for context — stop the thing first, ask afterward. And with repeated behaviour you have already inquired about, further questions become theatre; deliver the verdict.