Prov. It is more important to treat people well than to be good-looking.; Just because you are good-looking does not mean you are a good person. Jill: I'd like to get to know George better. Jane: Why? Jill: He's so handsome. Jane: Handsome is as handsome does. He's a very unpleasant person.
How one acts is more important than how one looks. For example, He may be homely, but he's the kindest man I've ever met-handsome is as handsome does. This expression already appeared in John Ray's 1670 collection of proverbs.