Ads are the most frequent answer, but it's not the only one. There's also the team getting acqui-hired, or getting bought by a competitor & shut down, or just p

Ads are the most frequent answer, but it's not the only one. There's also the team getting acqui-hired, or getting bought by a competitor & shut down, or just plain old going out of business and sold for parts. None of those are good for users, obviously, but they are all viable paths for repaying VCs in absence of a business model.