The document discusses the product life cycle and its four stages: introduction, growth, maturity, and decline. It explains that in the introduction stage, sales and profits are low as the goal is to create product awareness and trial. In the growth stage, sales rapidly rise as the goal is to maximize market share by offering extensions and penetrating the market. The maturity stage sees peak sales and profits as the goal is to maintain market share. Finally, in the decline stage, sales and profits fall as the goal is to reduce costs and retain loyal customers.