In the product life cycle the decline stage is the stage in which a product's sales decline. it can occur for several reasons which are following:
a. Increased competition. b. Shifts in consumer tastes. c. Technological advances.
Firms ought to be aware that carrying a poor product past its useful life may be very costly to the firm in several ways. Companies have to pay more attention to their aging manufacture. Decisions that need to be made are following:
a. The firms can decide to maintain a brand without modification in the expectation that competitors will leave the industry.
b. Managers can decide to harvest the manufacture (which means dropping various costs and hoping that sales hold up).
c. Managers can decide to decline the product from the line (liquidate it or sell it at salvage value).