One of the things we urge Y-Combinator companies to do is to have profitability in grasp. If you need to get profitable before your A round of money, you ought to be able to do that.
All companies that grow really big do so in only one way: people recommend the product or service to other people.
I don't invest in companies where my mental model is that they need to get themselves acquired in the next few years - or ever.
Many of the companies in the mobile location space are trying to figure out different ways to tie what they're doing to commerce.
I always tell my partners that our job is to fund all the companies we can that can be worth $10 billion or more. That's such a difficult constraint, we can't have any other constraints.
There is a long history of founders returning to companies and doing great things. Founders are able to set the vision for their companies with an authority no one else can.
The point of an accelerator is to teach you about companies and business, not about technology.
Being a public company is really terrible for most companies. I'd say Facebook and Google have done a pretty good job of standing up to the incredible quarterly pressure to hit numbers, but most companies - and I've observed a lot now - don't do a very good job of that.
Companies generally work better when they are smaller. It's always worth spending time to think about the least amount of projects/work you can feasibly do, and then having as small a team as possible to do it.
The way to build billion dollar companies is to first build something people love. There isn't really a shortcut there.