Why POS Systems Fail When Connecting to Large Rewards Catalogs

https://www.bookmarkpage.win/how-a-200m-retailer-overhauled-stackable-promotions-to-cut-checkout-confusion-by-80

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