system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: how does putting a plastic bag on your atm card help it read when it's having issues?

This is our go-to solution at work for getting troublesome cards to read, but no one seems to know why it helps.
gpt
Imagine there was a scratch on the painting in front of you.  You know how you can deliberately make your vision fuzzy?  Imagine doing that.  You still see the painting, but no longer see the scratch.  Of course, you the painting is a bit fuzzy, but everything is RELATIVELY in the same place.

That's all the card reader needs.  For everything to be in relatively the same place in proportion with everything else.  The plastic bag "fuzzies out" the scratch.

Edit: Thanks for the gold, kind stranger!