And they are surprised that no one wants to listen to them outside of that room either. Become a performer. There's no practice like the real thing. When I was a young student, I was overwhelmed with the prospect of trying to become a great player. That means, if you want to be a great player, you can be.
Dedicated practice is the key.
Practice the fundamentals of performance, technique, and sound production. Finally, we have all been at the place where we doubted whether we were practicing the right things, or even getting any better. I am convinced that if you practice the basics diligently and daily, you will become better. And in time, you can become great. It's actually harder to do so, and not get better.