“Good Enough” will mean that an autonomous car will be effectively useless between 6 and 8 months of the year in the north. Most of the roads may be clear, but

“Good Enough” will mean that an autonomous car will be effectively useless between 6 and 8 months of the year in the north. Most of the roads may be clear, but “all” of them never are. Shaded areas are the worst, and can remain iced over for months at a time. Ice, especially intermittent ice, is bad. Slush, deep snow, and packed snow can be miles worse. Winter driving, as any Californian who has migrated north will tell you, is a dramatically different skill than driving on the roads of California or Arizona. It’s non-deterministic - turning the wheel doesn’t always turn the car. The car will move sideways on the road with no steering input. The speed of the wheels is completely divorced from the speed of the car.