Why do you use a perforated plate at the bottom of a pressure cooker?

A perforated plate at the bottom of a pressure cooker is used to prevent direct contact between the heat source and the food being cooked. This helps distribute the heat evenly and prevents hot spots, reducing the risk of scorching or burning the food. The perforations also allow steam to circulate freely, aiding in the cooking process and helping to build and maintain pressure inside the cooker for faster cooking times.