All musicians have some of the same requirements of practice. Primarily, to know what you don’t know. In other words, you need to somehow become aware of what you need to develop to meet your goals.
Band members should be willing to encourage and assist the other players in the band to be their best. However, the band leader and/or the other band members should not need to inform you that what you are doing is not cutting it.
It is much better when you realize this on your own and admit it quickly.
There have been a few occasions where I needed to change a line or part of a song, or even drop a song from the list because I was unable to play it properly. Sometimes it is a speed issue; sometimes a memory issue.
Certainly, I am spending time working and improving, but I do not need someone else to tell me where I am failing.
I know what I don’t know. So should you.