To me, the cautionary warning (echoing Andrew Chen's[1]) for consumer startups was key: Beware too of the edge case where something spreads rapidly but the chu

To me, the cautionary warning (echoing Andrew Chen's[1]) for consumer startups was key: Beware too of the edge case where something spreads rapidly but the churn is high too, so that you have good net growth till you run through all the potential users, at which point it suddenly stops Sean Ellis[2] has a similar test for product market fit (the 40% rule): I ask existing users of a product how they would feel if they could no longer use the product. In my experience, achieving product/market fit requires at least 40% of users saying they would be “very disappointed” without your product. [1] http://andrewchen.co/2012/06/20/quora-when-does-high-growth-not-imply-productmarket-fit/ http://andrewchen.co/2012/06/20/quora-when-does-high-growth-... [2] http://startup-marketing.com/the-startup-pyramid/ http://startup-marketing.com/the-startup-pyramid/