You will not live enough to learn everything. Eventually you have to say "I could figure [something] out but I won't take that time." Most things are that way - I probably could learn brain surgery (I used this example because it has a reputation of being a very difficult course of study). I would like to make a lathe from scratch - but I don't have easy access to enough iron ore to get started - even if I start from scrap metal, I probably wouldn't spend months making my own surface plate (...) and so I own a factory made lathe instead.

That is why I'm content to delegate to agents - I have more code/features I want to write than I have time to debug (writing is the easy part).