Practicing hard only when the coach is looking is training yourself to perform, not improve.

Effort aimed at being seen and effort aimed at getting better look almost identical from outside and produce different results. One of them optimises for the appearance of work, which means the reps you do alone are the ones that actually move your level. Performing well in practice is a skill, just not the skill you were trying to build.

Do one session this week where nobody can see you and count what you get through. If the number drops a lot without an audience, that is your information. Train the unwatched version until the gap closes.