We have all heard the saying that birds of a feather flock together, meaning that the company you keep reflects your personality.
A smart person surrounds himself with other smart people.
When we were younger, we were most likely warned by our parents to be careful of whom we choose to spend our time with.
They said this in reference to the way others would judge us in accordance to our friends, in addition to the influence our friends would have upon us.
After standing there gaping for a few seconds I realized this was kind of a trick question.
It's equivalent to asking how to make a startup succeed — if you avoid every cause of failure, you succeed — and that's too big a question to answer on the fly.
And this form of list may be more useful in practice.
It's easier to catch yourself doing something you shouldn't than always to remember to do something you should.
In a sense there's just one mistake that kills startups: not making something users want.
If you make something users want, you'll probably be fine, whatever else you do or don't do.