Some level of integration, testing always has to meet the real world. Maybe in IT we would call a "canary" instead of a test. I once had a colleague who had

Some level of integration, testing always has to meet the real world. Maybe in IT we would call a "canary" instead of a test. I once had a colleague who had been a test driver for a major European car firm. His job was to drive cars around in real traffic. Self-driving cars need this all the more, since most of the hard and scary stuff is the integration of many systems and how they deal with unexpected scenarios. And worse still -- in a traditional car, you had an expert test-driver like my friend who could, say, take evasive action if the brakes didn't work. But in these cars, the driver is the system-under test.