Seatbelts do save lives. So, why do some people think that seatbelts can hurt you? One common belief is that a seatbelt might trap you in a car that's on fire or underwater. However, car accidents in which the car is on fire or submerged in water account for less than one half of 1 percent of all car crashes (source: Just Drive PA). When you think about it, wearing a seatbelt greatly decreases.