No, it’s not required. The poultry muscle contains around 75% moisture. As the proteins contract and release the juices as they cook, that liquid will help steam and cook the chicken. A small amount can help the meat stay moist, and you can use the residual juices to make gravy. Add 1/4 cup of liquid per pound of chicken, but it will take slightly longer to cook since the liquid needs to heat up before cooking the meat.