Many foods darken after cooking. The higher pressure and temperature of pressure cooking can darken them.

Oven cooking is a non-pressurized method of cooking that cooks slower through convection and radiant heat methods. Pressure cooking is a pressurized, fast cooking method that speeds up the cooking process. If you have the time, oven cooking is preferred, but if you wish to save energy and time, pressure cooking is the way to go.

cooking food faster than conventional cooking

because it might turnout really pretty or perfect.

in slow cooking the meat has a longer cooking time in pressure cooking the meat or whatever gets more tender and tastes better.