This article is mainly about why "growth hacking" is nonsense but half way through, Josh Elman @joshelman is quoted. What he says about growth and how to achieve it is succinct and I agree wholeheartedly.
Our name for Josh's "atomic unit of growth" is the "1.1 effect". Quite simply: does each person using our product get more than one other person to join before they leave? If not, go try again until they do.
It has always been our contention that we should spend NO money on marketing until we have that behaviour. We will simply be spending good money after bad.
However, when 1.1 is happening...
Josh Elman, who worked on growth at Twitter before joining Greylock as a VC, believes that word-of-mouth remains the fundamental principle of sustainable growth on the Internet. While “there’s lots of stuff that layers on top that aren’t pure word-of-mouth” he says, “the atomic unit of growth is one person talking about a product to another person. It doesn’t matter if it’s an app, a new restaurant, or new toothpaste.