As the market matures and growth slows, stars can transition into cash cows. Cash cows are business units or products that generate consistent, high profits with low investment needs. They are characterized by having a high market share in a low-growth industry. When stars become cash cows, the focus shifts from aggressive investment to maximizing efficiency and profitability. The revenues generated from cash cows can then be used to support other business units, including new stars and question marks.