Why do people hate hate subbed and dubbed so much?

I'm listening to comments from a lot of people as of late saying "sub is the best way to watch and dub is trash" or "dub is superior cuz subs are cringy" I really don't get why a lot of people heavily prefer one to the other, a lot of subs look really nice and sound really nice, but a lot of dubs also look and sound really fluent.