Getting benched is information delivered in the most uncomfortable available format. Nobody enjoys it, and the first response is usually about fairness rather than about content, which is understandable and also means the information goes unread. From the sideline you can see the whole shape of the game, including the thing you were doing wrong that was invisible from inside it.

When it happens, watch instead of sulking, then ask afterward what specifically would change the decision. Take the answer as a list rather than a verdict. Most coaches will tell you plainly if you ask in a way that shows you want to know.