However, why not charge on day 1? It sounds like something people should pay for. And charging always makes it clear if people really like your service or not.
We've been struggling with the question of when to monetize since there are also some strong points in favor of waiting. Some of those include avoiding a local maximum by way of pigeonholing yourself early, making it easier to reach scale and get feedback from a broader market, etc.
We'd love to hear your thoughts on this.
edit: To clarify, we have two monetization strategies that we think are especially viable—the question is when should a startup pull the trigger on their monetization strategy.
Some of the most successful companies, like Google, Facebook, Twitter, and Reddit, didn't charge on day 1.
Some of the most successful companies, like HP, Microsoft, Apple, and Adobe, changed on day 1.