Product depth refers to the variety of options available within a specific product line. For example, a brand like Nike may offer different styles, colors, and sizes of running shoes. This variety allows customers to choose products that best meet their individual preferences and needs. Having greater product depth can enhance customer satisfaction and loyalty, as it provides more choices. However, it can also complicate inventory management for retailers, as they must stock a wider range of items. Balancing product depth with other factors, such as product breadth, is essential for effective marketing and sales strategies.