Three Safety Bins: road testing doesn't get you all the way to "safe"

There are three bins for self-driving car safety: 
(1) Obviously dangerous
(2) NOT obviously dangerous, and
(3) Safe.

Road testing and driving scenario coverage can help you get from bin 1 to bin 2.

Getting to Safe (bin 3) requires a whole lot more. That's because it requires handling rare, unexpected, and novel events in both the equipment and the environment.