Hmm, maybe Bob should improve his social skills and be more kind. But I would talk to the team first and to him as well, maybe he doesn't realise that the work is not enjoyable if he doesn't put more patience and kindness into discussions.

Recently, I had a little incident with one teenage student. He has been a bit demotivated in general lately so it's more difficult to work with him as he doesn't want to put any effort to learn challenging pieces. One day I played him several different pieces and wanted him to choose which one he likes, but then he just left the lesson before it finished and without greeting me, leaving me with the impression that I did something wrong. Like he went out angry and with anxiety, his mother was present and he showed disobedience to her as well. His reaction was quite immature. So I immediately called the director of the school and reported the thing and the next week when he came to his lesson I talked to that student. I told him it is not the way our lessons should go and if he doesn't like something it's better he tells me immediately or even better - quit the piano lessons completely as I also want to enjoy my work and I don't want to work in this way. So, he changed the attitude the same day 😆 and now we have again enjoyable lessons ;)