Transfer

Six boxes leave the warehouse for the shop. A transfer is what says so while they are on the van.

Why not two adjustments

Adjusting stock down at one end and up at the other gets to the same total, and loses the only thing worth having: the link between them.

With a transfer you can answer the question that actually comes up. Twelve left, ten arrived, so where are the other two? Two adjustments cannot tell you whether they were never sent or never unpacked.

Treat the far end like a delivery

Count what arrives against what the transfer says was sent. It is receiving with a different supplier, and the same rule applies: count the boxes, not the paperwork that came with them.

Where it goes wrong

Transfers stay open. Stock shows as in transit for weeks, so it belongs to neither location and is not sellable at either. A store with eight open transfers has a stockroom full of goods its own website will not sell.

The other one is transferring on the day the boxes are packed rather than the day they leave. Anything that then gets pulled out of the box is missing at both ends, and it turns up later as an inventory adjustment nobody can explain.