How stock on hand is worked out
Every movement is recorded, and the quantity is the sum of them — the number on the product is a cache of that sum, not the truth.
MOTION keeps a ledger of stock movements: received on a supplier invoice, sold on a job, adjusted by hand, counted in a stocktake. The quantity you see on a product is the total of that ledger. It can always be rebuilt, and a movement is never deleted.
What moves stock
- Processing a job card or invoice takes the parts off.
- Voiding one puts them back.
- Processing a supplier invoice brings them in.
- A hand adjustment, which always requires a reason.
- Applying a stocktake.
Nothing moves stock while a document is a draft. A job card sitting open with six parts on it has not taken those parts off the shelf — which is why the shelf and the screen can disagree until it is processed.
- Negative on hand
- The books think you sold more than you had. It is a counting error rather than a stock level, and it is left visible rather than clamped to zero so it can be found and fixed.