Returns, and putting things back
Customer returns are the most common way stock records gain phantom quantities that are not there.
A customer returns an item. It is refunded, put back on the shelf, and somewhere in that sequence the stock record either does not change or changes twice.
Once workload is measured, the useful next step is to change the process rather than simply count it. For a broader optimisation example, see this page.
Returns are the messiest movement in a small business because they run backwards through a process designed to run forwards.
Separate the refund from the restock
These are different decisions and combining them causes most of the errors. Refunding the customer is a financial transaction. Returning the item to sellable stock is a stock decision that depends on its condition.
An item refunded and binned should reduce stock by nothing and increase it by nothing. An item refunded and resold increases stock by one. Systems that restock automatically on refund get the second case right and the first case wrong, permanently.
The default should be that returned goods enter a holding location and are only moved to sellable stock after a check. Automatic restocking puts damaged items back in front of customers.
Receiving and putaway also have a safety dimension; OSHA warehousing guidance summarises common warehouse and material-handling hazards.
Give returns a location
A physical holding area — a shelf, a labelled box — prevents the two failure modes: returns sitting in a corner unprocessed for weeks, and returns going straight back onto the shelf unchecked.
Record the reason
Faulty, wrong item sent, not as described, changed their mind, damaged in transit. Each points somewhere different — quality, picking accuracy, product description, carrier.
A return rate with no reason breakdown is a number that can only be worried about. With the breakdown it is a list of specific fixable things, and picking errors in particular are usually cheaper to fix than anyone expects.
Watch for the same item returning repeatedly
A line with a return rate well above the rest is telling you something: the description is misleading, the sizing is wrong, the quality is poor, or it is frequently mis-picked.
This is visible only if returns are recorded against the item rather than only against the order.
Decide what happens to unsellable returns
Every business accumulates returned goods that cannot be resold and have not been disposed of, because nobody decided. They occupy space and are counted at each cycle.
A standing rule — repair, discount, return to supplier, dispose — applied at the point of inspection rather than deferred, is what keeps that pile from becoming permanent.