That and other reasons. Difficulty learning—among other cognitive limitations—is also a prominent reason why those who dedicate most of their time to doing so are often ostracised by large groups of people.
Discussion
Maybe if school wasn't SOOOO bad -children could learn, but the truth is too steal their energy to learn bull$h!t that doesn't matter in life. Think about it, how exhausted (mentally) were you when you came home from school?