We need a fixed quantity item capability in bills of material and production orders.
There are cases where you need X amount of an item no matter what the production order quantity. For example we use 1 of a component no matter if we run 1 or 100 of the parent item for the standard bill of material.
For Production Order Bills of material:
We also at time would use this to add additional quantities to an order manually in cases where we may have scrap or need to substitute or add some of a component without the restriction of a quantity per.
Another example is the need to add more of an item to get a specific property for the final item and it is not a quantity per., we see this alot in recipe type product where you may need to add more of an ingredient to get to a desired PH or specific gravity or even for ice cream a specific milk fat percentage.