I remember when I was a kid, people asking a teacher how to spell a word, and the answer was generally "look it up in a dictionary"… which you can only do if you already have shortlist of possible spellings.

*nix man pages are the same: if you already know which tool can solve your problem, they're easy to use. But you have to already have a shortlist of tools that can solve your problem, before you even know which man pages to read.