Every few months there is a recall here in the USA because the ‘P’ (Park) setting in automatic gearboxes has been failing. Those affected vehicles that haven’t also had the parking brake properly set will then inevitably roll away down any hills or even the gentlest of slopes they happen to be on, and then they build up momentum. This frequently results only in damage but all too often this can maim or kill pedestrians…. especially children playing on driveways or in nearby yards!
Here’s just one example: Another half-a-million vehicles recalled in the USA
Vehicles can even cause harm if left on totally flat ground at the roadside, without a parking brake in use, if they are hit by another vehicle. Think of billiard balls. Your car’s “P” setting will be smashed by any hard impact and your car will then careen away until it runs out of momentum or it hits something.
The humble parking brake is one of the most undervalued and most abused safety controls found in modern vehicles, and this failure to understand and the resultant failure to actually use parking brakes leads to many pointless and preventable crashes, some of which cost lives.