The most important aspect of the Packing List for the system is that it lets us manage our stock of products or services . As we have seen previously, we can't base the stock management on Sale or Purchase Order. In the company's business life, there will be many reasons why we won't deliver or receive goods or services which have been ordered. We can't base the stock management on the Invoice module either. Once again, there will be many cases when we will deliver or receive goods or services which won't be invoiced.
The only way to keep track of the stock is then to use the Packing Lists.
Packing Lists are used when we prepare the goods to be sent to the customer, or when we receive the goods from a supplier. We have the Order document, so we know what should be sent/received. As we have seen previously in the tutorial "How to create Sale Orders", in ERP5, the confirmed Order will automatically generate a Packing List for the following trade process.
Then we will prepare the goods and validate the Packing List. If we follow what was planned in the automatically generated Packing List, everything is fine. But if we don't send the correct quantity, we can still change it on the Packing List.
Similarly when we receive goods after sending a Purchase Order, an "expected" Packing List is generated. When we receive the goods, we can compare it with the Packing List of the supplier , to see if the goods we received are the same as on the paper. Then once we verify the goods, we can correct the received Packing List if required.
In one word, by using Packing Lists, we will have a better stock management.