As you start building the product, don't assume that you...

As you start building the product, don't assume that you know all the answers. Listen to the community and adapt. We had a lot of our own ideas about how the service would evolve. Coming from PayPal and eBay, we saw YouTube as a powerful way to add video to auctions, but we didn't see anyone using our product that way, so we didn't add features to support it.