Why do I currently trust any contactless payment terminal to debit the right amount from my Visa card ? The trust is built with every transaction. The first t

Why do I currently trust any contactless payment terminal to debit the right amount from my Visa card ? The trust is built with every transaction. The first time I used one of those strange little white terminals it seemed a bit dodgy ... but you pretty quickly come to trust that what's on the screen is what gets debited. Also I doubt Apple would leave a nice app-accessible text field on the Tap To Pay dialog where I can insert my fake amount. Right ?!