Article implies without stating outright that the driver was working a night shift, which are problematic for sleep schedules across a wide range of industries.

Article implies without stating outright that the driver was working a night shift, which are problematic for sleep schedules across a wide range of industries. People fall asleep at night, even when they are expected by their bosses to be alert. Waymo responded by walking back their cut of safety drivers from 2 to 1, but only for night shifts. If you tell someone that they will be fired the literal instant they doze off, all you are doing is guaranteeing that they will get fired, especially when you also task them with a boring job and ban all means by which they might boost their orexin levels during their shift. That is one of the hormones that regulate alertness, and responds to mental engagement. It cycles up and down with the circadian period. The result: bored at night; out like a light. The occupants of a self-driving vehicle will fall asleep at night. If you aren't testing that use case, you aren't doing your job. Managing alertness levels at night is the company's problem. Bright lighting with plenty of blue light in the spectrum is part of it. Keeping the employees from getting bored is, too. Sleep countermeasures will have to be installed with user-monitored car automation, and the safety-driver/tester just saved Waymo from a future liability nightmare. Why are they no longer with the company?! I think one solution may be to gamify safety-driving such that the human safety for an autonomous driver earns points for vigilance-related tasks. Identify potential road hazards before the autonomous system does. Count blue cars. Play the 49-state license plate game. Play a trivia game over the audio system. Hear about local points of historical interest near where you are driving. Anything other than silently watching moving road lines extend beyond the range of your headlights.