A leasing company must create a binding contract with a customer because they are agreeing to buy the car from the dealer for a specific price. The only reason they are willing to buy this car on your behalf is because you have agreed to rent it from them at a premium price. It is a different way for a bank to earn interest on their capital, which is how they make money.
The problem a bank has is that not all customers are able to continue making payments through the term of the lease, which creates a lease default.
Banks worry about lease defaults because they own the car, which means they now have to assume a loss on the vehicle because it is no longer earning interest payments on the lease. Therefore, the bank will make every effort to ensure you continue to make your payments as promised!
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