If you ask someone questions, ask out of curiosity, not out of judgment. They will be much more open/receptive to honestly answering your question AND potentially working on a solution with you if you are asking in a way where it isn’t questioning their decision-making skills.
If you come off as judgmental, the other person will shut down and become defensive (this is the reason I avoid phrasing a question as “why did you do that this way?”). Instead, try to ask open-ended questions and start off on the right foot.