Why do people fix their openbite?

Orthodontia: Orthodontia or surgery depending on the diagnosis.

Looks and function: Usually only two reasons to fix it. They don't like the way they look or are tired of not being able to use their front teeth.

Function usually: Think of the teeth as part of a tripod. The back teeth on either side stabilize the tripod but need that third stabilizer: the front teeth. Also think of a refrigerator on one foot, angled. It will harm the floor with too much weight. Set fridge on all feet and adjust them and the floor is unharmed. Weight or functional distribution of forces is why. Cosmetics too!

Open bite: Better facial harmony, better biting and chewing.