Why Did Google Decide To Split Inbox From Gmail?

A couple of years ago, right around the time Google’s Gmail team decided to start working on a standalone email app, the recently announced Inbox, a major redesign of Gmail was launched. As is the case with all Google products it was first released internally as “dogfood” to let Googlers themselves digest all the new features, or as was the case with this particular redesign, the removal of most of the advanced features.