One of the few lessons I learned at work is the importance of knowing what you don't know. I remember assuring the state specialist for Arkansas of an answer, which I wasn't really sure of. Naturally I was wrong, and the answer turned up in an OIG report.
Seems to me the same issue is cropping in with self-driving cars, as witness this Technology Review article on problems with the new Tesla software/hardware. Apparently Google is trying to handle all situations, but the problem drivers are having with the Tesla is not knowing when the system is approaching the limit of its capability, i.e., not knowing what the Tesla doesn't know or isn't sure of.