Should you try to change the person you love?

Most believe one should love a person for who they are and not try to change them. I disagree. I believe, you should try to change them to become a better person. If you don't try to change them then you don't care about them. If your child starts smoking then would you say that you love them for who they are and therefore, would not try to change their habbit of smoking? No, you try to change them because you love them and care about them.