The definition of a startup is a reoccurring theme here and I'd really wish pg would reference it every time he uses the term. For him, a startup = growth [0], and as you can tell by this quora answer[1], not everyone agrees with that.

[0] - http://www.paulgraham.com/growth.html

[1] - https://www.quora.com/What-is-the-proper-definition-of-a-sta...