There's a large and perhaps unsolvable problem of the state of the art solutions that doesn't get nearly as much attention as it should - even if the car can safely handle 99% or 99.9% of the situations, the algorithms are not really able to detect if they're in the last 0.1%. The car will slam into stationary trucks, suddenly brake for no reason, consider the tollbooth to be a bus - all with utmost confidence it's doing the right thing.

In other words - the value of proposition of autonomous driving would be completely fine if the car gives up on unarguably difficult situations and alerts the driver to take over. As of now, however, the car will boldly do something stupid and dangerous.