Yeah, this type of advice rubs me the wrong way: I feel like the author is thinking of "hard" as though it were back-breaking day labor that any fool could do, but nobody wants to because it's so unpleasant.

The sort of people it's usually directed at, though, are knowledge workers (like computer programmers). "Hard" in our context is "something I don't yet know how to do". Always. No exceptions. Every time. If I know how to do it, it's trivial. If I don't, I have to figure it out.

And in my experience, the "do the hardest thing" VC-founder cheerleader types (who are always telling you, never themselves) absolutely lose their shit when they see somebody trying to figure out how to do something. Reading docs? Setting up controlled experiments? Why are you wasting time with all of this nonsense and not just getting to the "hardest thing" so I can bill the client and you can move on to the next "hardest thing"?