Why POS Systems Fail When Connecting to Large Rewards Catalogs

https://www.bookmark-step.win/when-maria-watched-conversions-slip-away-a-checkout-story-about-speed-and-sandbox-illusions

When a point-of-sale (POS) terminal suddenly starts rejecting coupons after a rewards catalog expansion to more than 2,800 items, it feels like the store's checkout plumbing burst. The error doesn't announce itself as "catalog too big