In your opinion, of course. There are some classics out there where a respected, talented actor takes a truly awful role. There's a famous story about Kim Basinger agreeing to appear in a film called Boxing Helena and then realising what an utter turkey it was and breaking her contract. It cost her a fortune but her reputation remained intact. I'll go for something slightly more obscure here. Mickey Rooney in Breakfast at Tiffany's. "Miss Gorightry!" Dreadful.