Would you ever tell your kid that you didn't like their SO/tastes in SOs?

This was a thought that crossed my mind in the shower. Might not be the most controversial, but I figured I'd give it a go.

Maybe the SO in question is a heavy drinker, a heavy smoker, has a DUI or two, doesn't seem like they're doing anything in their life, has cheated in the past, or has a really dark and messed up sense or humor and loves to make offensive jokes around you and your family, whatever the reason, you don't like them. However, your kid looks past all of that and loves them.

Do you ask your kid why they are with them? Tell them that "they can do better," or, encourage them to think about breaking up with the SO? Or, do you just keep those thoughts to yourself and try to grow to love them?

Would your answer change if you were dealing with a teen rather than an adult?