Stock and production

Stock is where implementations most often go wrong, because it is the only area where the system can be contradicted by physical reality. An invoice cannot be disproved by walking into a room. A stock figure can.

One idea underneath everything

There is no “stock level” field in Odoo. Stock is the sum of all movements in and out of a location.

Every receipt, delivery, transfer, adjustment and production consumes or produces movements, and the quantity you see is calculated from them. Once you accept this, most stock questions become answerable: if a figure is wrong, some movement is wrong, missing or duplicated, and you can go and find it.

The second idea follows from the first: a stock movement is usually a financial event too. Goods arriving increase the value of your inventory. Goods shipped become cost of sales. That link is configured in the product category, and it is the single most common source of “why does stock not match the accounts”.

Before — on paper 7 steps

1. The customer asks whether twenty units are available.
2. The salesman telephones the storekeeper.
3. The storekeeper walks to the aisle and counts what he can see.
4. He does not know that twelve are already promised to another order.
5. The salesman promises twenty and confirms the order.
6. On the delivery day, eight units are missing.
7. The customer is telephoned, the order is split, and the delivery is late.

A promise made from a number nobody actually had. It costs a delivery, and sometimes the customer.

After — in Odoo 3 steps

1. The salesman types the line and sees on hand, reserved and forecast together.
2. The twelve already promised are excluded automatically.
3. If the quantity is short, a replenishment is proposed there and then.

Sales promise from the same figure the warehouse works from, because it is the same figure.

What to learn, in order

Locations and warehouses. Physical places, arranged in a tree. Odoo also uses virtual locations for things like production, scrap and inventory adjustment — which is how it keeps every movement balanced between two places.

Operation types. Receipts, deliveries, internal transfers, manufacturing. Each has its own numbering and behaviour.

Multi-step flows. A one-step delivery just ships. A two-step picks then ships. Three-step picks, packs, then ships. Match the number of steps to how the warehouse genuinely works — adding steps that nobody performs is how you get a system people bypass.

Replenishment. Reordering rules with minimum and maximum quantities, and make-to-order. Understand the difference before a client asks for automatic purchasing.

Lots and serial numbers. Essential for food, pharmaceutical and anything with a warranty. Decide early: turning tracking on after go-live, with stock already on hand, is unpleasant.

Adjustments and counting. How physical counts get entered and what they post. Clients will do this monthly, so it must be simple for them.

Manufacturing

Start with a bill of materials and a manufacturing order with no routing at all. Get that working and understood before adding work centres, operations and time tracking.

Things to understand early:

• BoM types — normal manufacturing versus a kit, which is not manufactured at all but exploded at delivery.
• Components consumed against components planned, and what happens when they differ.
• Subcontracting, where someone else manufactures for you.
• Work centre capacity and cost, which is where manufacturing meets costing.

Where beginners go wrong

• Designing the warehouse the client asks for instead of the one they operate. Ask to walk the floor.
• Too many steps. Every extra step is a screen someone must complete, every day, forever.
• Turning on lot tracking late.
• Ignoring valuation until the accountant appears in month four with a stock figure that does not match the ledger.
• Complex routings before basic manufacturing works.
• Forgetting scrap and returns. They are always needed and always remembered late.

Practise this

1. Build a warehouse with two locations, receive stock, transfer between them, and deliver.
2. Switch delivery from one step to two, and see what changes for the user.
3. Set a reordering rule, run replenishment, and follow the purchase order it proposes.
4. Enable lot tracking on one product, receive two lots, and deliver a specific one.
5. Build a two-level bill of materials and manufacture the top-level product.
6. Do a physical count that disagrees with the system, post the adjustment, and find the accounting entry it made.

Exercise 6 is the important one. If you can explain what an inventory adjustment did to the general ledger, you understand something most people implementing Odoo do not.