you own a car

your car gets stolen

the car then gets ringed

and sold on

this seller can lose the car if it's found out unless they repay the insurance company if it's had a pay out on it, unlikely as you wouldn't want to be twice for the same stolen car

if this seller then sells it on, the next buyer is free of any repercussions and can keep the car

happened to a few mates of mine on more than one occasions, biggest loss was £3k when he bought a ringer, but i told him it was a ringer when he went to see it and he still spent money on it so it's his own stupid fault when the old bill came and relived him of it two weeks later