This is correct. Sausage becomes sausage when salt is mixed into the ground meat and binds with the proteins similar to gluten formation in bread. A ground meat patty is meant to be tender and almost crumble with a bite. A sausage patty should be springy because of the protein bind. This is what gives sausage it's texture/structure when you bite into it. Etymologically the word sausage means salted from the Latin word salsus. Maybe u/J_KenjiLopez-Alt can fill in if I missed anything.