Listen and follow the leader

I love playing with others, beginners too, but become frustrated when the proper chord progression isn't followed and the player doesn't seem to know it. Eye contact with the person leading the song and listening is so important. If you can't hear the other players turn yourself down. Also annoying to me is when the song leader/vocalist is interrupted by another who either doesn't follow the song and verse structure intended by the leader, or worse deliberately derails the song, taking it somewhere else without so much as a wink or a nod of approval first.
And as mentioned, not tuning their instrument to the circle. The circle could be out, but playing together fine. Hendrix played intentionally tuned flat.

So that's my beef. And I agree with most of the above, but I do think there can be value in playing rhythm chops quietly along with advanced players.