One of the questions that has puzzled many Facebook users is why the company decided to split out the messaging component into a separate, standalone app. At a live Q&A session, Facebook's Mark Zuckerberg finally revealed why the choice was made.
It all comes down to the user experience, Zuckerberg explained. He said that while Facebook's primary purpose is to serve you the News Feed, messaging is a feature that people were using more and more. "You're probably messaging people 15 times per day."