text: A driveless car is very expansive because they have to know the roads, when to stop, how to stop, or when to go. It stated " These smart-road-systems worked surprisingly well, but they required massive upgrades to existing roads, something that was simply too expensive to be practical." Driveless cars work well but they are too expensive because they have to know the upgrades of roads. Imagine the cost you have to pay for the car, giving them their money back for the money they spent and work they spent putting into the car. Sensors are a very big issues too in driveless cars.