@azaman17 There's a lot that goes into auras being unlocked. Training, Traumatic events, Even before birth. However, when it comes to the military, it comes down to quality and quantity. There's no telling how long it will take to unlock aura. Days. Months. Years. it all depends on the person. And even after unlocking aura or discovering a semblance, there's no telling if it will be useful or a liability. An example would be Qrow's semblance. It seems easier just to train some grunts to fire a gun than train their aura.