i think because Hyundai is a bad car? there shouldn't be much you can do about it except to sell it off and get a better car.
that was what i did to my previous Hyundai, and i know i never will get such junk again.
At the end of you wiper arm there is aplastic cover pry open there your see a nut can't remember the size , but just tighten the nut on both arms. I have an 2001 should be the same.