Back orders

A cost incurred by a business when it is unable to fill an order and must complete it later. A backorder cost can be discrete, as in the cost to replace a specific piece of inventory, or intangible, such as the effects of poor customer service. Backorder costs are usually computed and displayed on a per-unit basis.
Backorder costs are important for companies to track, as the relationship between holding costs of inventory and backorder costs will determine whether a company should over- or under-produce. If the carrying cost of inventory is less than backorder costs (this is true in most cases), the company should over-produce and keep an inventory.
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