When Grant was in the beginning of his acting career (after graduating from Oxford College) he struggled with roles as small time crooks. His acting was convincing so he got stuck with that type of roles for quite some time. He actually made a statement right before "Four Weddings and a Funeral" opened that if the movie flopped he would retire from acting. It isn't hard to understand that he kept using the winning formula, the shy British man, once he discovered it.