Originally Posted by
FearFree
I've had a card get declined on the first try, and work on subsequent tries. My card was fairly well worn, and the magnetic strip didn't read well. Some merchants it worked fine, other times it must have only read the partial numbers and at these places would come back as declined. A 2nd swipe often resulted in an approval, and if not a manual entry of the card number would always result in an approval. It wasn't usually a problem except for the one day at McDonald's when the cashier was adamant that she couldn't manually enter the numbers.
The card has since been replaced, but it is certainly plausible.
You can also have them run it backwards. The computers read the magnetic strip the same forward and backward. As someone else pointed out running it slowly usually works.
I had some guy in front of me once hold up the only line to call the credit card company and make a big show out of getting them to approve charges when he was obviously over his limit. He made it out like he was some big shot and was looking around the whole time as if to say DYKWIA....very annoying. And the cashier did NOTHING.