Sales inventory systems are often standardised i.e. A business will adopt a general model for their own use. This means that they are able to track sales of a product and match it against their existing inventory to regulate how much stock they keep to hand and how much it costs them to do so. Obviously this is necessary for any business in order to run efficiently. However, adopting a general model means that it may not be optimised for the particular stock/business in question. For example, if you run a food business then whether or not the food is perishable will effect how often your re-stock your inventory and how cost effective it is to keep large amounts of food in stock. A sales inventory system quickly becomes very limited if the type of stock being sold isn't taken into due consideration.
