What is the meaning of sunk cost? What is the difference between sunk and the relevant cost of product ,support the answer with example?

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A sunk cost is a past  cost which is not directly relevant in decision making  eg development costs which have already been incurred. The principle underlying  decision accounting is that management decisions can only affect the future.

A relevant cost is a future cash flow arising as a direct consequence of a decision. eg relevant costs are future costs

They are 2 distinctive types of costs that firms frequently incurre in the running of business. *Sunk costs reflect expenses that have already been incurred and arose as results of designs taken in the past. ,for example purchase a software program for $200,however it doesn't work as the company intended to use, and the seller doesn't offer any refund,and doesn't accept any retains.,so this cost has alreadybeen incurred and can't be recovered. *Relevant cost is a managerial account term descries past costs that aren't used to make current business decisions. *For example, if a rubber t yre company receiveda request to provides a price quote for an order to supply of 1000 custom made tyres requiredfor industrial vehicles.,so the companyis facing stiff competition from its business rivas and hoping to securethe order

In economics and business decision-making, a sunk cost is a cost that has already been incurred and cannot be recovered. Sunk costs (also known as retrospective costs) are sometimes contrasted with prospective costs, which are future costs that may be incurred or changed if an action is taken.

Costs incurred in the past for the acquisition of an asset [or a resource] are called sunk costs. They cannot be changed, no matter what future course of action is taken because past expenditures are not recoverable, regardless of current circumstances. After an asset or resource is acquired, managers may find that it is no longer adequate for the intended purposes, does not perform to expectations, is technologically out of date, or is no longer marketable. A decision, typically involving two alternatives, must then be made: keep or dispose of the old asset. In making this decision, a current or future selling price may be obtained for the old asset, but such a price is the result of current or future conditions and does not “recoup” a historical cost. The historical cost is not relevant to the decision