How do people become better looking as they mature ?

As you gain confidence your body language radiates with a positive attitude. Smiling faces are better looking. That's another example of a body language change that maturity brings. Teenagers are sometimes embarred to smile because they are uptight. As you outgrow being a teenager your skins clears up from acne and dandruff problems seem to disappear. When your body becomes fully grown it all fits together like a puzzle. Up until then some body parts are awkward. But as you said, everybody doesn't get better looking as they mature unless they take on a new respect for their face and body. That does include proper nutrition and exercise something you also learn as you grow up.