I had a Math professor in college who used to say amount of effort almost doubles if you wish to score a few extra marks above some point. Like say if the you

I had a Math professor in college who used to say amount of effort almost doubles if you wish to score a few extra marks above some point. Like say if the you are already scoring 80/100. Going to 90 will almost take same the effort it took going from 0-80. Going 5 more marks higher will mean a similar long slog effort. It was simply his way of saying doing big stuff required insane amounts of effort. Often not justifiable. I have seen something similar in competitive programming too. After a while solving regular problem gives your very little exposure in return, to keep your returns coming, you have to up your problem difficulty level at every step. And that consumes time.