Xavier Amatriain's answer to Where is Machine Learning or Artificial Intelligence adding value to your company? - Quora

For a product like Quora to succeed, it needs to manage three different aspects well: user engagement, quality of the content, and monetization. The first one should be obvious: a product cannot grow unless users find the content they read and the product itself engaging. The second one, quality, connects directly to our mission to share and grow knowledge. Content needs to have a certain degree of quality to even qualify as knowledge. Not only that, we actually want users to engage in reading and writing good quality content, because that is the only way to scale our knowledge platform.