Firstly, jim bob, you should be asking "Why so?" and not "Why not?". Once you have chewed on that a little bit, and taken your two hour nap to recover from your ensuing mental fatigue, chew on this:
You see jim bob, you cannot prevent a crime *after* it has been committed. So, to prevent a crime, you'd need to track data so that you can have a chance of preventing it.
Further, jim bob, whose data would you track after the crime has been committed? "The evil doer"'s presumably. buttuming you can identify who that is, jim bob, it makes sense that you need to track them earlier. Even Seeker the stupid unpleasant woman would agree, so do not disappoint me here.
Since this is going to be a major overload for that peanut rattling inside your huge melon of a cranium, figure this: If Atta's car-to make it easy for you, the evil doer's car-was equipped with such a device to track data, it would make zero sense to turn on the tracking *after* the plane had hit the building.
Raise your hand if you got lost in the plot somewhere, and I'll send Gomer to render some brain-to-peanut resus...
