The damage is that &quot;getting money back after the transaction wasn&#x27;t finalized&quot; wasn&#x27;t a consensual part of the contract.<p>You buy a car from me. A -month- later I show up and say, &quot;Yeah, sorry, I sold this car by accident, here&#x27;s your money.&quot; and I take off with the car regardless of what you want to do, you have a case against me for theft.<p>Whether the buyer got his money back is irrelevant - that doesn&#x27;t give the seller the retroactive ability to void the sale.