Agreed. If your product just works, “sales” is a piece of cake. If it doesn’t and you find yourself hiring a fancy expensive charismatic sales team just to convince people to buy your product then that’s borderline fraud imo.
I've had trouble getting big companies to buy startup product because a) nobody wants to be the first big name and b) they're worried you'll be out of business in 2 years and integration effort will have been for nothing.
Of course these are self-fulfilling prophesies unless you can get the "engine" running.
Also if your product overlaps with features or products of a large vendor who already has a relationship with your customer (this is common) you have to fight the incumbent - and they have home team advantage even if their product sucks.