Katherine Heigl and Shonda Rhimes
We all know that nobody likes Katherine Heigl. She's difficult to work with, rude, and selfish. Shonda Rhimes, writer and creator of Grey's Anatomy, probably regretted ever letting Heigl on the cast. Heigl publicly said that she was never given good material to work with and insinuated that Rhimes' writing was poor. Needless to say, there was no contract renewal and she was gone within a year and a half.