A transfer is a document, not an adjustment
Goods leaving one location and entering another go through a transfer with its own state: what was sent, what was received, what is missing. The two movements are linked, so you cannot have an issue without its receipt.
The usual alternative — subtract from warehouse A, add to warehouse B, by hand — produces exactly the discrepancy nobody can explain three months later.
Bins inside the warehouse
Within a warehouse, goods sit in bins, and scanning works with them. For a physical count that is the difference that matters: you count a bin, not the whole building.
Worth knowing
A company with two stock locations has, in practice, three stock figures: A's, B's and the ledger's. When the transfer is a document, the three cannot diverge — because they are the same record seen from three sides.