And deep in their dark hearts the Orcs loathed the Master whom they served in fear, the maker only of their misery.
-
Silmarillion; Of the Coming of the Elves and the Captivity of Melkor
See 'Melkor'. It will there be seen that the wills of Orcs and Balrogs etc. are part of Melkor's power 'dispersed'. Their spirit is one of hate. But hate is non-cooperative (except under direct fear).
Hence the rebellions, mutinies, etc. when Morgoth seems far off. Orcs are beasts and Balrogs corrupted Maiar. Also (n.b.) Morgoth not Sauron is the source of Orc-wills. Sauron is just another (if greater) agent. Orcs can rebel against him without losing their own irremediable allegiance to evil (Morgoth).
-
Myths Transformed; VIII; Orcs
They were certainly dominated by their Master, but his dominion was by fear, and they were aware of this fear and hated him. They were indeed so corrupted that they were pitiless, and there was no cruelty or wickedness that they would not commit; but this was the corruption of independent wills, and they took pleasure in their deeds.
They were capable of acting on their own, doing evil deeds unbidden for their own sport; or if Morgoth and his agents were far away, they might neglect his commands. They sometimes fought [> They hated one another and often fought] among themselves, to the detriment of Morgoth's plans.
-
Myths Transformed; X; Orcs
It is true, of course, that Morgoth held the Orcs in dire thraldom; for in their corruption they had lost almost all possibility of resisting the domination of his will. So great indeed did its pressure upon them become ere Angband fell that, if he turned his thought towards them, they were conscious of his 'eye' wherever they might be; and when Morgoth was at last removed from Arda the Orcs that survived in the West were scattered, leaderless and almost witless, and were for a long time without control or purpose.
This servitude to a central will that reduced the Orcs almost to an ant-like life was seen even more plainly in the Second and Third Ages under the tyranny of Sauron, Morgoth's chief lieutenant. Sauron indeed achieved even greater control over his Orcs than Morgoth had done.
...But [Sauron] had also inherited from those days difficulties, such as the diversity of the Orcs in breed and language, and the feuds among them; while in many places in Middle-earth, after the fall of Thangorodrim and during the concealment of Sauron, the Orcs recovering from their helplessness had set up petty realms of their own and had become accustomed to independence.
Nonetheless Sauron in time managed to unite them all in unreasoning hatred of the Elves and of Men who associated with them; while the Orcs of his own trained armies were so completely under his will that they would sacrifice themselves without hesitation at his command.*
(* [footnote to the text] But there remained one flaw in his control, inevitable. In the kingdom of hate and fear, the strongest thing is hate. All his Orcs hated one another, and must be kept ever at war with some 'enemy' to prevent them from slaying one another.)
-
Myths Transformed; X
Morgoth though in origin possessed of vast power was finite; and it was this expenditure upon the orks, and still more upon the other far more formidable creatures in his service, that in the event so dissipated his powers of mind that Morgoth's overthrow became possible.
Thus the greater part of the orks, though under his orders and the dark shadow of their fear of him, were only intermittently objects of his immediate thought and concern, and while that was removed they relapsed into independence and became conscious of their hatred of him and his tyranny. Then they might neglect his orders, or engage in [text end]
-
Myths Transformed; X