Another trope that hasn't been mentioned:

The Jerk Ass is temporarily replaced, to the relief of the other characters, but that replacement cannot last due to exigent plot circumstances. When the Jerk Ass returns, the other characters are not pleased to lose the erstwhile replacement. This negative reaction to the Jerk Ass' return may lead to the Jerk Ass self-reflecting upon his/her past behavior, and/or may lead to the other characters scheming to bring back the replacement on a permanent basis.

(I'm new to the site; I don't want to ruffle any feathers by editing the main page out of turn, so I'm posting this here instead).