Gameplay: Vehicles - why do they always explode?

[DviddLeff]

Why do vehicles in PS and other games always explode when they run out of hit points? (obviously to save on clutter and reward people killing them)

However what if this wasn't always the way it worked in PS2, some of you will remember the "Your vehicle is out of control" mechanic in PS that had a chance of occurring when your vehicle dropped below 10% health, which many were annoyed about as it basically removed 10% of the life of a vehicle.

Now in PS2 we have vehicle hit locations, so why not have different vehicle "death" depending on the last place hit? Now while I don't think the World War II Online systems detail is needed, a simpler version would surfice to add some very cool elements to the game:

Ground Vehicles
Track/wheel/hover pod: vehicle can no longer move, but can be repaired.
Turret: Ammunition explodes, destroying the vehicle.
Engine: Vehicle disabled, fire starts and will lead to explosion.
Crew compartment: crew killed, vehicle remains relatively intact.

Air Vehicles
Engine: Vehicle loses power as then engine burns, will fall from sky.
Weapon hard point: Explodes, destroying the vehicle
Cockpit: crew killed, vehicle crashes.

Now you could go to town with this and have individual engines stop working while the pilot tries to control it with the other one, or individual tracks and wheels breaking allowing the driver to move the vehicle with the remaining ones.

Here is the system WWIIO has: