Mark Zuckerberg: “The best levers for growth are often within the product itself.”

Making it so we could grow faster was, I think, the most important product feature that we ended up building for Facebook. And, you know, the traditional approach to growing and marketing is you have a communications group or you have a marketing team and you buy ads, and sometimes there's a place for that, especially when you're trying to communicate something and get a message out. But if you're actually trying to grow a product, I think often the best levers for doing that are within the product themselves and getting people in your community who enjoy what you're doing to evangelize that to their friends and getting that to happen as efficiently as possible. So there's no magic in the growth group that we built that other people can't replicate. It's just being very rigorous with data, investing in data infrastructure. So that way you can process all these different experiments and learn what people are trying to tell you and then go invest engineering and actually try to grow the community. Because I think that's the most important feature for a lot of networks.