It happened in high school. I wasn't ready to go to university - as I had no idea what I wanted to do - so I made the decision to stay behind an extra year. In retrospect, it was a very good decision - otherwise I'd probably be in an expensive aviation management program at another Ontario university, with a larger than normal tuition fee due to the price of Cessna fuel.
That being said, there was a moment in high school in which I woke up and became aware that I was ready to move on; I was done with high school and was ready to become a university student with the university style of learning; the same thing has happened with me and university. I'm not quite done with university at this point, but I am getting awful tired of classroom based learning.
I think a lot of the fatigue and burn out is due to my exchange - not the quality of teaching, but things I've been exposed to, and things I've learned outside of school. Where would I want to go from university though? I'm glad you asked - I'd like to go back into university but in a different context; I'd like to go into research.
Research based learning is an exciting prospect to think about, because it's no longer learning to "catch-up" to mainstream knowledge, it's learning for discovery and that's a thing that gets me excited.
I'm not entirely finished with classroom based learning at this point - it has its places, but I'm just really hoping to offset it with some research when I return for my 4th year of University... and beyond.
P.S. I've attached a picture of me at the most beautiful beach ever in Koh Phi Phi - you should be jealous. :)