In his e-mail, Mr. Westin said, “There are some other things I want to do professionally — things that I cannot explore while fulfilling my responsibilities here.”Of course, it's never as simple as that. Most reports say Westin was forced out because he wasn't forward thinking enough. Again, from the NYT:
[An] ABC News staff member informed of the decision said that Disney and ABC managers had pressed Mr. Westin for years to make the division more profitable, but had been unhappy with his efforts to accomplish that goal. ABC announced in February that it would reduce its staff by up to 400 employees, about 25 percent of its work force.