The social atmosphere, usually created by the earliest patrons of a place, is what draws in other people.
Any good club promoter knows that the best way to get cool/good-looking/rich people in the door is to have other cool/good-looking/rich people already inside. This lesson, however, does not receive its due in talking about our social networks. At a recent Google event, Jess Lee, the founder of Polyvore, a social shopping site, placed some of the blame for Google Plus' male-skewed site by noting that the "seed" of the site came from the company itself. Here's what Wired Business heard:
I have one theory, just a theory, I think the seed of that community is very very important. Polyvore was seeded on fashion forums. Google+ was actually seeded with Google employees, so it was tech, and honestly mostly male. That's part of how it grew -- those people invited their friends. Facebook started at colleges... Myspace probably started with music. It's all about the seed, and the seed for Google+ was different.
All too often, we come to technological or even biological explanations for why a particular social network is popular among a particular group of people. Women love Pinterest because of their brain chemistry! Women love Pinterest's simple and clean interface! Etcetera.
But what if the answer is simple and human, rather than complex and technological. What if it was Pinterest's seed that created a community that was both welcome and welcoming to women? The site's early heavy users were largely young women drawn from non-coastal areas. They set the site's tone, which then began a self-reinforcing process of more women gathering because more women were already gathered.
Obviously, there are a lot of reasons why social networks (like restaurants or other social institutions) succeed. But focusing exclusively on technology is like thinking only the restaurants with the best food succeed. The social atmosphere, usually created by the earliest patrons of a place, manufacture the glue that draws in other people.
All that to say: Choose your beta testers wisely.