You ordered 24 units of a top seller. The box shows up, your team unpacks it, puts it on the shelf. The invoice says 24. You pay for 24. But there were only 20 in the box.
Four units at $15 wholesale is $60. Multiply that across 30 vendors and 4 buying seasons. You're leaving thousands on the table every year and you might not even know it.
It's not malicious, it's just nobody checking
Vendors don't usually short-ship on purpose. Warehouses make mistakes. Items get backordered and nobody updates the paperwork. Sizes get substituted without a heads up.
The problem isn't bad vendors. It's that when your receiving process is "unpack the box and put it on the shelf," nobody catches the gap. By the time you notice, the invoice is paid and the vendor says it's too late.
Where the missing units actually go
Most shorts fall into a few buckets. A size or colour was backordered at the warehouse and the packing slip was printed from the order, not from the box. A substitution went in and nobody wrote it on the slip. A split shipment went out in two boxes and the second one is still coming. Or the picker miscounted, which happens more than anyone at the vendor will admit.
Each of those has a different fix. A backorder needs a date or a cancellation. A substitution needs a yes or a no from you. A split shipment needs the balance kept open, not written off. A miscount needs a credit. You can only ask for the right one if you know which bucket you are in, and you only know that if someone counted.
What to write down at the dock
Keep it to what you will need in an email to the vendor. For each line: what you ordered, what came, what arrived damaged. Who counted it and the date. A photo of the packing slip and one of the box before it is broken down. That is the whole record, and it takes less time than re-shelving the four units that never arrived.
Do it against the purchase order, not against the packing slip. The slip is the vendor's story of what shipped. The PO is what you agreed to pay for. The gap between the two is the number you are looking for.
The fix is embarrassingly simple
Count what's in the box before you pay the invoice. Open the PO on a tablet. Check each line. Tap to confirm. If 4 units are missing, you know right now, not 3 weeks from now.
Invoe flags the discrepancy the second it happens. Ordered 24, received 20? It's marked for follow-up before the invoice is due. You have the documentation to go back to the vendor while it still matters.
Talk to the vendor while it still matters
Most vendors will make a short right if you tell them within a couple of weeks and you have the paperwork. Send the PO number, the packing slip, your count and the photo. Say what you want: a reship, or a credit against the invoice. Ask which it will be and when.
What does not work is the call in month three, when the invoice is paid, the season has moved on and the rep has changed. At that point it is not a short shipment anymore. It is just money you spent.
A partial shipment is not a short shipment
The two get confused, and the confusion costs money in the other direction. If the vendor tells you the balance is coming, keep the order open and hold it to the new date. Do not close it and reorder, or you will pay twice and get two boxes. Invoe keeps the balance open on the same PO, so the second box checks in against the same order and the count closes itself.
The math is obvious
Retailers tell us short shipment detection alone pays for the tool. You're catching $50-100 in discrepancies per shipment across dozens of vendors. It's not exciting work, but it's the kind of thing that protects your margins quarter after quarter.