The decline stage is the fourth and final stage of the product life cycle. Its entry is generally caused by technology advancements, consumer or user preference changes, global competition or environmental or regulatory changes. In this stage, sales and profits slow down and eventually decline as the product becomes obsolete. As a result, the company may decide to discontinue the product or try to revive it through rebranding or repositioning. During this stage, companies must carefully manage their costs and inventory levels to minimise losses.