Does teenage acne really disappear when you become an adult?

My nephew is a boy, and he has some acne all over his face.

My sister has skin that sometimes gets pimples during her period, but

I wonder if my nephew inherited it, because he has acne...

However, when I look at the adult men around me, there are hardly any who have acne.

So, I suddenly got curious: does acne really almost disappear once you become an adult?

Otherwise, I wonder if everyone gets treatment...