A small communication breakdown is enough for everyone to be working on slightly different things. And then you loose focus.

If you're not in college and you don't know a cofounder, the next best thing I think is to go work at an interesting company.

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

... and you can only have 2 or 3 things everyday, because everything else will just come at you; you know fires in a day.

It's better to have a few users love your product than for a lot of users to sort of like it.

A board member of mine used to say sales fix everything in a startup, and that is really true.

Keep salaries low and equity high. Keep the organization as flat as you can.