There’s a good reason why Elon Musk spends so much time musing about driverless cars, even as he is hard pressed to deliver the next generation of Tesla’s human-driven electric vehicles.  It is the same reason that General Motors announced its$500 million investment in Lyft just days before CEO Mary Barra unveiled the new Chevy Bolt and, a few weeks later, bought the assets of Sidecar, the failed car-sharing innovator. It is why Travis Kalanick, CEO of Uber, poached 40 top scientists and researchers from Carnegie Mellon University to develop Uber’s own driverless capabilities—at the risk of ultimately alienating the human drivers upon whom Uber’s current business success depends.