Because of the nature of human beings, no one can deal with more than a handful of employees directly. For a CEO, it is impossible to even meet them let alone supervise so many ... hence, the hierachical structure of all large scale human endeavors.

The few at the top must make only general orders. These are meted out to the closest subordinates who then transmit those orders to their subordinates along with their interpretation of the general order. They make it somewhat more specific. The aspect of the order which will impact their subordinates is the interpretation specified. These then interpret these specifics and transmit to their subordinates an order yet more specific and tailored to what aspect affects them. And so on down the hierarchy till the lowest rank and file is given the most specific order which he must interpret for himself so as to impliment his particular piece of the grand original order.

By way of example:
Abe Lincoln tells George McClellan to prosecute the war with more vigor. "End it as quickly as possible."

He doesn't tell McClellan how to do it.
McClellan decides to implement the Lincoln order by "taking Richmond".
He then tells his generals what he intends to do but not exactly how to do it.
They then interpret the order in light of their own experience and issue still further orders to their subordinates and so on until every aspect of the original case is covered ... inclusive of all logistics.

Here is where the system comes unravelled.

Of course, everybody knows this. Or do they?

If at any point in the hierarchy, orders are given of excessive specificity the subordinates receiving them cannot interpret according to their own experience and present knowledge. The issuer of such a too specific order is in effect saying that he has greater knowledge than his subordinates ... in the area of their expertise.

Of course, this is impossible in most situations. One man can know about a million things. His ten subordinates know ten million things (with some overlapping). Hence, they must have a greater combined knowledge in the area of their expertise than their commander. By "forcing" a specific direction on them he loses that expertise and ties them to a level of competence only equal to his own knowledge and expertise. If he carefully issues orders with the proper mix of generality and specificity appropriate to his place in the hierarchy, he magnifies the efficacy of his judgement ten fold.

See?

Failure to make proper use of one's subordinates will undo any large scale human endeavor.

What would cause "the general" to issue imperial orders?

What surprises me over and over is the prevalence of imperial orders at every level of activity ... and ... the failure to recognize them . Even "the mob" issues such orders to itself in a democracy.

There is an optimum balance to be struck in transmitting orders down the hierarchy between generality and specificity. Whomsoever best achieves this balance takes the field.

And ...there is a reverse principle in transmitting information up the hierarchy. The commander receives information from his subordinates, generalises it and sends it further up the hierarchy with his interpretation. If the balance is again correct, the general's decision making process is based upon accurate knowledge.

If this knowledge proves to be inaccurate, there is a method of acquiring good information by random sampling of the lower subordinates (the general can't talk to every private). But consistently bad information is the result of the same problems in the hierarchy as above.

Come to think of it, imperial orders are the inverse of random sampling. Neither works as a best case method. They are what one does, for good or ill, in the presence of a non-functioning hierarchy.