Can someone explain eyesight/vision problems/glass/blindness to me?

I have gotten glasses a year ago and I know the glasses are making my vision worse. Same goes for all people who get glasses and that’s why they need to get a new prescription every year.

So, I may be paranoid, but if my eyes will consistently get worse every year, how come I won’t end up blind?

Or what about people who have had glasses since they were kids, how come they are not blind yet? Or are they going to become blind?

I’m worried 🙁 If glasses make your vision worse, how come people get them and optomologists’ do what they do?