Bugs-in-production Memes

When your grocery store's pricing system runs into JavaScript's favorite number: NaN (Not a Number). Someone tried to calculate a discount percentage and the system just went "nope, can't compute this" and slapped it on the sign anyway. The discount shows "-NaN%" which is technically accurate—you're getting negative Not-a-Number percent off, which is somehow still 45p for a kiwi. The real comedy gold here is that NaN appears TWICE—once in the discount bubble and once crossed out next to it. It's like the system tried to fix its own mistake, failed, then just gave up and printed both. Classic error handling: when in doubt, display everything and let the customer figure it out. Fun fact: In JavaScript, NaN is the only value that's not equal to itself. So NaN === NaN returns false, which means this discount is literally incomparable to itself. Schrödinger's sale price, if you will.