How Coin Trick Works
The coin trick is simple but very effective. The perpetrator inserts a small coin or any other thing into the door handle mechanism; it often causes the failure of the lock to engage properly, and when the owner departs, he may believe his car is locked up, while in reality, the door remains unlocked.

This method makes it difficult for the thief to break into the car later. At times, by the time the owner gets back, the car could be broken into without any evident signs of being forcefully entered. It is a bright subtle method through which tiny distractions are exploited.