A loss map: at which stage goods 'disappear'

When a warehouse finds a shortage, the first question is usually "who took it?" Often the right question is a different one: "at which stage?" Goods do not vanish in an instant. They may have been miscounted at receiving, put in the wrong bin in storage, handed out by mistake at picking or sent out without paperwork at dispatch. At each stage the loss looks different. That is why a shortage is better viewed as a map than as a list.

What the map is

A loss map is a one-page diagram of the warehouse. It sets out the goods' path in order: receiving, storage, picking, dispatch, returns. For each stage four things are recorded: who works there, what document is raised, what check exists and where the chance of loss is higher. The map is made not to find someone to blame but to see the weak point in the process. A hand-drawn table is enough; no complex software is needed. Involve people from every stage: the receiver, storekeeper, picker and driver know best where their own work is difficult.

Typical sources by stage

Receiving

• goods are accepted without counting, only against the paper;
• damaged or poor-quality goods are not recorded separately;
• the supplier's document and the actual quantity differ, and nobody writes it down;
• the receipt document is raised late.

Storage

• goods go into the wrong bin and effectively "disappear";
• a pack is opened and partly used, but the remainder is not recorded;
• the shelf life runs out or goods spoil from damp;
• people with no business in the warehouse walk in and out freely.

Picking

• the wrong item code is taken while the right one stays on the books;
• an incomplete pack is sent out;
• samples or goods for internal use leave without a document;
• goods from one order end up in another.

Dispatch and returns

• there is no check at loading and pieces are not counted;
• the document says one thing, the truck holds another;
• returned goods are accepted but not put back into the balance;
• the document is not signed with the driver or forwarder.

Much of this is error or disorder, not intent. If unauthorised removal or theft is suspected, a map will not settle it: that calls for the responsible department and a lawyer.

How to build the map

1. Follow one order or one pallet from start to finish.
2. At each stage record who touches the goods and what document is written.
3. Mark where a check exists (count, signature, scanner) and single out the places without one.
4. Take the shortage list from the last count and place each item at its most likely stage.
5. Fix first the stage where the most items have piled up.

A hypothetical example

At the last count a shortage was found on 40 lines. Spread across the stages, it came out as: receiving 9, storage 11, picking 14, dispatch 6. Picking took the largest share, so it is reviewed first: checking the item code with a scanner and a separate document for samples. The figures are invented.

Low-cost control points

Once the map is ready, weak spots can get a control without much expense:

• counting goods at receiving and photographing damage;
• confirming bin and goods with a scanner;
• a second check of the item code at picking;
• another person counting at loading;
• a separate zone and document for returned goods.

Most control points take a few minutes, yet show the shortage before the goods leave the warehouse. And when each point is confirmed by a signature or mark, responsibility becomes clear too.

After the map

The map fixes nothing by itself; it only shows priorities. Besides the stage with the most lines, high-value goods matter too: one expensive line can cost more than a dozen cheap ones. Give each fix an owner and a deadline, and at the next count fill in the same map again. Where the figures fell, the measure worked; where they did not, look again. That turns the map from a one-off sketch into a working tool.

Conclusion

A loss map replaces the question "who is to blame?" with "where is the weak point?", which opens the way to a fix. In a warehouse audit, Inventory analyses the processes, helps find the causes of losses and gives recommendations for improving efficiency.