> 9 times out of 10, the "correct" advice to give your friend on their startup/product is to deliver a completely filter-free structured rant about all the ways their startup/product is complete and utter dogshit.

But see it's more complicated than that.

I would say it's way more likely that the best advice you could give someone working on a new startup or product is to to convince them to stop being so negative and stop thinking everything they're doing is dogshit and to summon the self-confidence and charisma that comes from really believing in what you're doing, since that tends to have self-fulfilling effects.

Unless, of course, the person has delusional self-regard already, and are more likely to make the opposite mistake.

One reason why giving advice is so challenging is that it's always extremely context-driven.