Most Helpful Girl
I asked this a while back. The consensus was they ripped off people's songs and seem to always be playing the same kind of one song over and over again... and that it's popular to hate them.
But underneath that - the main singer and some of the other guys are (it seems) frat bros who are incredibly sexist, immature for any age, especially their age, rude to a lot of people, especially women and they're just overall not great human beings.
(Chad even payed one man in some country to stick his penis in a hole full of razor blades and then laughed when the guy did it and pulled it out bleeding profusely... The dude thought it was a joke, but Chad knew it was real... still laughed.)1