When a debit card can't be read by a machine, why does wrapping plastic or paper over the card make it work?

Question

It's odd, some brands of interac machines read my bank card just fine, while others always get a card problem. But wrapping a receipt or a grocery bag over the strip solves that problem. Why is that?

Answer 1

It is helping to create static electricity. This makes it easier for the machine to read the magnetic data stored on the stripe.