Conversation so far:
Is there anything special revealed about Andy Bernard's character in Season 3?
Early season episodes reveal Andy Bernard's anger issues, displayed when he finds his calculator encased in Jell-O.
Does Andy Bernard have any rivals at work?
There is rivalry with Dwight Schrute over whether Andy Bernard's title is higher than that of Dwight's Assistant Regional Manager, fueling an intense power struggle.
Does Andy Bernard leave his job at any point in Season 3?
A producer's cut of the episode explains Andy Bernard's departure from subsequent episodes as due to being sent to anger management training.
When does Andy Bernard rejoin his job?
Andy Bernard returns a few months later to a short-lived three-year shunning courtesy of Dwight Schrute.
Who else does Andy Bernard work with at his job?
Andy Bernard accompanies Jim Halpert to meet with clients from a local high school following an obscene watermark being vandalized onto Dunder Mifflin paper.
Does Andy Bernard have any emotional problems at work?
Jim Halpert hides Andy Bernard's mobile phone that rings with Andy's rendition of Rockin' Robin in the ceiling, enraging him into punching a hole in the office wall.

Question: Is this the reason that Andy has to leave his job?
Self-contained rewrite: Is punching a hole in the office wall the reason that Andy Bernard has to leave his job?