That largely depends on the coach, but I think it's generally true for the better coaches. The question regarding X's and O's is how quickly they take advice from their assistants/stats guys, and how good they are at improvising.
Right now, Green is slow to make long term strategic changes, and that includes rotation decisions. Last season he took until about 50 games in to realise who should actually be in the rotation, for example.
Hopefully he'll get quicker as time goes on.