I have a similar story as noduerme, but for me it was interest and laziness. I got by in all my pre-college math just by listening in class. But, if I couldn't connect it to something I found fun (like taking apart and putting back together my NES for the 100th time, or playing some sport), I just didn't do anything beyond the minimum. Then college came around, and I got an F in my first math course. I retook the course and found a teacher who connected most topics to gambling and/or business and I was hooked. I managed to take that teacher for almost all the math I needed for my CS degree :)