A difficult opponent can reveal a weakness practice had allowed you to overlook.

Practice quietly arranges itself around what you already do well. The drills you enjoy are the ones you repeat, and the gap goes unexamined because nothing in the routine presses on it. A genuinely hard opponent presses on it immediately. That is information about one specific thing, not a verdict on your ability.

After the next contest that goes badly, resist the global judgment and look for the exact moment it turned. Name the skill involved in a single sentence. Then build one uncomfortable drill around it and put that in the week rather than the parts you enjoy.