I'm not an expert on self driving cars, nor a rocket scientist, but the expectation that self driving cars will be perfected to be flawless under any road or weather conditions, able to go anywhere on the open road safely, for the occupants, as well as for other vehicles, pedestrians, bicyclists, even animals that may appear out of nowhere without warning, seems to be very pie-in-the-sky. Will these cars be able to react to problems that may occur way beyond the next car in line, at a distance that could be visible for a real driver to react safely to, or will it continue on into the car in front when that car finally collides with the pileup in front of him? What about animals that come running out of a field, down a ditch, then into the path, maybe even running into the side of the self driving car. What about inclement weather when a sudden blizzard pops up and all it's navigation sensors go into WTF mode? I live in a rural area and most all of the roads are either 2 lane, some paved, most are gravel; or just simply old narrow 2 track logging trails that requires the cooperation of each driver to negotiate head on passing at the widest available spot on the trail. How's the driverless car going to communicate with the opposite driver and determine the best spot to pass? What about the scenario of a parked delivery truck double parked on a city street. Will the WTF mode sensors kick in and simply block all traffic behind the car, being unable to decide what is best, where to go, what to do?
I don't think the designers and programmers will be able to refine the required parameters to ever produce a safe, economical, self driving vehicle for real world driving. Perhaps on a closed course, maybe, but never within reason on each and every public road. Our roads and highways need continual maintenance to keep from deteriorating, and that costs a lot of money. Would the investment to allow driverless cars on our roads steal dollars from the road maintenance budget needed today?