It's pretty simple - most people do reject such businesses. You never see the businesses that people researched but gave up early.

Some people take the risk.

What happened to the good ol' "Don't put all your eggs in one basket" adage?

Optimists don't care about baskets because they don't believe their business is made of eggs.

Probably more like, put all eggs in one basket, then run like hell until the basket is too big to fail or someone buys the basket.

Gave a talk to this effect 5 years ago, to an audience including enthusiastic developers aspiring to found this new breed of startups. I expected my comments might be polarizing but instead of arguments got questions which seemed to indicate this was the first time they'd considered the question. It's not necessarily that people think it's a sane idea per se, but that they've become accustomed to the idea that writing code naturally requires approval of these gatekeepers as a starting point. I hope the ecosystem recovers.

I don't know. It seems like another risk to build in. They had the chance to make a big app and potentially be acquired by Facebook or someone. They didn't win enough people over to put the screws to Twitter, so they lost.

You can't accommodate a single point of failure when that failure is a guarantee that you business fails. The problem with making a business without a second source for your key dependencies is similar to the problem in the martingale[1] betting strategy; the failure mode means you're out of the game and you can't finish any strategy you may use to compensate for a failures.

> be acquired

Oh, that explains it. What you're describing isn't trying to be a successful business. Peasants creating an ornate trinket they hope will impress the local feudal lord is not a business plan.

[1] http://en.wikipedia.org/wiki/Martingale_%28betting_system%29

You ridicule it, and perhaps rightfully, but it's a pretty good way to make a lot of FU money to be able to turn around and flip off the 'feudal lords' after the handcuffs come off.