The cost of actually developing a driverless car entails more than financial risk. Apple has the money, but it also has to be calculated about what sorts of gambles it takes and when. Silicon Valley is already convinced that driverless cars are the future, but actually getting them on the roads—and not just test vehicles in Mountain View or in Austin, as Google has done—will still require surmounting enormous regulatory and technological challenges. “I don’t think anyone is clear, at the moment, on how autonomous driving is actually going to get introduced,” said Andrew Moore, the dean of computer science at Carnegie Mellon.