AI can detect financial fraud more efficiently than previous technology did, but it also flags legitimate transactions that it shouldn't. CardMapr.nl on Unsplash, CC BY Imagine you’re at the supermarket checkout. Your cart is full. The line behind you is long. You tap your card. Declined. You try again. Declined. You haven’t overspent. You haven’t done anything suspicious. But somewhere inside your bank’s computer systems, a machine made a decision about you in less time than it takes to blink