Elaboration for “Issuing of Inventory”

“Issuing of inventory
When the production department requests materials for production, they will send a material
requisition note to the stores.
The stores will issue the material and update the inventory records.
Any unused material will be returned to the stores together with a materials returned note and inventory records will be updated.”

Hi sir, please elaborate on the above.

Is it talking about factories here manufacturing goods ?
Are the stores the factories where the material is being created out of the machinery ?

I thought the Production Department would be within the factories creating the products from the machinery, instead of requesting the stores to create them.

Also, please if you could rephrase the process explained above in a more elaborate and simpler manner.

Thanks