When I was there, I wouldn't say it was "bad". No one did anything malicious or anything. It was mostly just extremely boring, like basically staring at the walls for days on end kind of boring. So yeah, it was bad, just not in the way that it's commonly portrayed in movies/shows.
Some of the patients who were there earlier told a story about how there was a guy who lost it in the day room over a chess game that he lost, started flipping over tables, just going utterly berserk. And tried to attack one of the patients. But I wasn't there when that happened.