It probably boils down to obligation or choice. I didn't like school when I was there, was always the kid being bullied, the slowest, the fattest, the stupidest, the one who forgot to do homework, the first to get punished for the same crime, etc.

Then decades after leaving school I went back to university, enrolled in an undergrad course, and absolutely love every lesson. They may be boring (stuff I learned 20 years ago), exciting (new discoveries taught to students nowadays that didn't exist when I was one), amazing (the "other" method)... but what really makes it fun for me is that I chose to be there.