Seat belts, crumple zones, air bags don't claim to prevent accidents. People aren't likely to say "Ah well, it doesn't matter I don't need to pay attention, sin

Seat belts, crumple zones, air bags don't claim to prevent accidents. People aren't likely to say "Ah well, it doesn't matter I don't need to pay attention, since I have an air bag". Radar etc though does claim to prevent accidents. Which will likely mean people pay less attention.