For some reason, I immediately groked calculus and why it would be useful (maybe because I liked physics and the relationship between velocity and position is an intuitive one), but the point of linear algebra was a complete mystery to me.

Why are we multiplying these big matrices of numbers, and what is this complicated determinant thing? Why would anyone ever care what a kernel is, and what are these subspaces that keep getting referenced?

Now every other somewhat mathy problem I see can be broken down into linear algebra and I wish I had learned it better (and that it was taught with more intuition).