Conscription is not good or needed, the modern military is equipped with a wide array of technology and the best training available, it takes year(s) to fully train a soldier. There was a time when you could hand a consript a gun and point him in a the right direction and you had an army, in a modern conflict that lack of training is lethal.

Also in an all volunteer force it's hard enough to manage groups who volunteered to be in the military, I can't imagine controlling people who were forced to be there.