<human>:  Why did Don Draper leave the agency?
<bot>: Don Draper left the agency because he was fired. He was a creative genius, but he had a bad temper and he was not very good at managing people. He also had a drinking problem and he was unfaithful to his wife. He was a difficult person to work with, and the agency was not happy with him. He was not a very good person, but he was a great advertising man.