1. The CEO loves to hear himself talk ... so don't speak while he is talking or he will get upset, tell you "This conversation this obviously over", and will leave your office pissed.
2. No room for error.... if you make a mistake, just resign that day. Don't think the CEO will even entertain an improvement roadmap.
3. The CEO is very reactionary so if you are applying for a leadership position, please don't.
4. It could be argued that the CEO's Assistant makes the decisions not him.