What I've learned from Numerical Analysis (and other parts of maths):

I want a formula to solve everything. But what I'm supposed to be learning is a process.

At lower levels, memorising formulae is all you need to do. Later on in life, however, things get a bit more complicated. All you are given is a general method, and you have to adapt it for specific situations.

I miss that magical feeling of plugging in a formula someone else discovered and Hey presto! Right answers where you need them.
But magic is hard to find in the real world.

And sometimes you have to be the one to discover the formula.