A payment API returns success. The interface turns green. Everyone relaxes.
But what exactly succeeded?
The payment rail may have accepted or settled money while the merchant never received the callback. Inventory may still be uncommitted. The selected variant may have changed. Fulfillment may not have started. A buyer or Agent may be staring at a timeout and deciding whether to retry.
In distributed commerce, payment success is one fact. Transaction completion is a chain of facts owned by different systems and people.
The green checkmark hides several clocks
