"Seven years ago, the idea that a car could drive itself wasn't much more than an idea. Chris has been a vital force for the project, helping the team move from a research phase to a point where this lifesaving technology will soon become a reality. He departs with our warmest wishes," reads a statement from an Alphabet spokesperson. Google's self-driving car project is one of the pet projects of X, the research arm of Alphabet.
According to the Times, Urmson had disagreed with the direction of the car project, and he made those concerns known to Alphabet CEO Larry Page and car project CEO John Krafcik a number of months ago. (Krafcik just joined the project last year after Google hired him away from Hyundai America.) However, according to Urmson, these disagreements were not the reason for his decision to leave the project.
"I have every confidence that the mission is in capable hands. There are many other problems or products this talented group of people could work on, but they've chosen self-driving cars because they understand the impact their work can have on making our roads safer and bringing everyday destinations within reach for millions of people. I will be cheering along and following their progress," he wrote.
Source : http://www.pcmag.com/news/346823/google-loses-car-project-cto