I think some business models only make sense at scale. While the caveat does apply to facebook (they probably could have been a profitable niche student social

I think some business models only make sense at scale. While the caveat does apply to facebook (they probably could have been a profitable niche student social network) occasionally I see businesses that it just doesn't make sense to even start unless you plan on getting really big. Examples would be PayPal, Google and Spotify.