Bear in mind that this advice is for companies in YC that are trying to raise a VC round. The failure rate in tech startups is so high that VCs are mostly only

Bear in mind that this advice is for companies in YC that are trying to raise a VC round. The failure rate in tech startups is so high that VCs are mostly only interested in investing in the potential to have an outsized Thielian-monopoly return, so that the very few winners in their portfolio can cover the many losses. It doesn't mean that this is the only way to run a successful business or that other ways are invalid or unprofitable. It just means if you want Silicon Valley VC, this is what that particular group of investors is looking for.