Most startups are not nearly focussed enough. They work hard...maybe, but they don't work hard on the right things.

... for the top twenty most valuable YC companies, all of them have at least two founders.

The startups that do well are the ones that are working all the time.

Most good founders that I know at any given time have a set of small overarching goals for the company that everybody in the company knows.

Investors will sort of like write the check and then, despite a lot of promises, don't usually do that much; sometimes they do.

In the beginning of a company, there is no management and this actually works really well.

A lot of people treat choosing their cofounder with even less importance than they put on hiring. Don't do this.