Guru devotion is a dead end, where you end up psychologically locked up.

Some people (devotees) don't realize it, and stay there, actually enjoying their prison's cell.

Some people try to get out of it, after they've realized they are not at the right place - or that there is something wrong there,  for various reasons, and/or after some bad experiences.

Getting angry is part of the exiting process (which has several other aspects) for many people.