I don't get why "Big O" is made out to be this mystical, theoretical thing. It doesn't seem as hard or as important as people make it out to be. I've been giv

I don't get why "Big O" is made out to be this mystical, theoretical thing. It doesn't seem as hard or as important as people make it out to be. I've been giving what you might call "enrichment" lessons to a friend in lambda school, and half an hour with a makeshift graph in Microsoft Paint ("Quadratic: BAD. Constant and logarithmic: GOOD. Linear: STILL PRETTY GREAT") was all it took. Like, sure, he's not going to be coming up with new compression algorithms any time soon, but... IMO the stuff that's harder to teach (and to learn!) are things that impact development velocity---how to write maintainable code, how to choose good design (and avoid bad!)---basically, taste.