When a discount does not apply, shows the wrong amount, or fires in the wrong market, and how to work out why.
A leaked code never announces itself. It just gets used more, from places it should not, and you find out from the margin weeks later. Here are the two signals that give it away early, and why the right response is an alert rather than a shutdown.
Shopify's checkout calculation engine can silently alter fixed-amount discounts by a few cents. Here's exactly what's happening, why, and what it means for your store.
The discount shows the wrong amount, fires in the wrong market, or does not apply at all. What causes each case on Shopify, and the fix for every one.