>The assumption is that the non-officers need to know what to do, but do not need to know why they need to do something.
I spent almost 2 decades in the Army. Its a terrible assumption. Except for combat situations, other emergencies, or really trivial tasks, everyone should know why they are doing something. It is physically impossible to make a non-stupid person care about a thing of which they have no knowledge. From my experience, the one thing that has the greatest impact on a person's ability to do a good job is a genuine desire to accomplish whatever their objective is. If they don't know what that objective is, they simply aren't going to give a shit. They might get it done adequately, but the military is a self-proclaimed meritocracy, so one would think that isn't enough.
It has been at least 50 years if not 100 since the majority of enlisted people didn't have a decent education. Now its incredibly common for enlisted Soldiers to have an undergraduate degree. Education isn't a guarantee of competence, intelligence, or even anything remotely useful, but that goes for officers and enlisted personnel.
Yet the military still insists on operating like they did in olden times when the average enlisted person was an illiterate farm hand. Their primary business is the physical enforcement of political interests (AKA combat), so in some ways it makes sense for them even though it also hurts them. However, businesses should be careful when evaluating their methodologies for civilian use, because there are certainly a ton of drawbacks.
The reason the US military is one of the most capable fighting forces in the world has more to do with technological sophistication (created by civilians) and a near unlimited budget than it has to do with the leadership of the military, the horrific bureaucracy that the leadership created/maintains, or the frequently alleged magical, inherent superiority of the American soldier.