Simple systems for moving people that have been around for a while still have "bugs" and issues which bedevil them. Think ski-lifts or subway trains. Self-driving cars in traffic are WAY more complex.
- Potholes and debris.
- Flat tires and mechanical problems.
- Snow and ice. Hurricanes and tornados.
- Parking vs. empty vehicles on the road.
- People driving in competition with driverless cars (game theory).
- Solar flares disrupting GPS.
- Power outages resulting in dark traffic signals.
- Pit-stops.
- Real-life distractions (noise in passenger compartment) and dilemmas (double-bind, Sophie's choice, et al).
- People j-walking, riding bicycles, etc.
- Insurance? Whose fault is it when mishaps hap?
