Why do Marketers use perceptual maps as a means to display or graph in two dimensions the location of products or brands?

The main reason for this is to try and position their brand or product in the best way possible within the market. Perceptual maps allow marketers to see how individuals are perceiving the competitive brands as well as their own brands, the markets use this information to determine which position will best benefit their brand in the market and hopefully beat the competition.