These three conditions for creating virality were listed on Founders Notebook a month or two back:
The most powerfully growing products do three things at once:
1.They make you look smart to the people you invite.
2. They give real value to you when the people you invite join.
3. They give real value to the people you’ve invited once they sign up.
As with my post yesterday, these are all about understanding and respecting your customer. Respecting that they will only do things if it makes sense for them and understanding what will make them look smart, what will give them value and what will give their friends value.
There’s no substitute for understanding customers.