Should I prick sausages during cooking?
A very simple answer why you prick sausages. When the sausages get heated up, the fat content and also air pressure inside start to grow. Pricking sausgaes allow the air and fat to be 'released', otherwise, the skin of the sausages will start to crack which eventually will result in losing more juice and 'fat'.

Yes, Pricking may lead to dry sausages, so you don't have to overdo it and also use the small toothpick to do it which will reduce the damages.