Most stores that process more than a handful of returns use a portal: the customer starts the return, prints a label, and the app tells Shopify what to do when the parcel arrives. Part of what it tells Shopify is "restock this."
That instruction is sent and forgotten. The app's job ends when the return is marked complete. Whether the inventory count actually rose is not something it goes back to check.
Why a sent instruction is not a moved count
A restock can fail to land for ordinary reasons. The location it targets might not stock that item. The variant might have been edited or deleted since the order. An API call might have errored after the return was already marked done. A staff member might have adjusted the count by hand in the meantime and undone it without knowing.
In every one of those cases the returns app shows a tidy, completed return. Your inventory still reflects the sale.
The check
For each return your app marked as restocked in a period:
1. Note the variant, quantity, location and the time the return completed. 2. Look at the inventory history for that variant at that location. 3. Confirm there is an adjustment of the right quantity, within a reasonable window after completion.
If there is no adjustment, or it is smaller than the quantity, or it landed at a different location, that unit needs a decision.
Doing this at scale
By hand this is a spreadsheet exercise, and Shopify's inventory history in the admin is limited in how far back it shows. The practical version is to record each restock claim as it happens and then watch for the matching adjustment. A claim with no adjustment after a day or two is your exception.
This is what StockReclaim's Rule D does. It records the claim from either a refund or a return, waits for the inventory level to rise, and lists the ones that never did. It runs alongside AfterShip, Loop, ReturnGO or any other portal, or alongside none. Learn more about restock claimed, stock unchanged.
A note on trust
None of this is a criticism of returns apps. They do the customer-facing part well. But an audit is a different job from an operator, and the operator cannot mark its own work. Someone has to check.