It could be that the Jailer was a servant of the Arbiter that was punished to lord over the maw for a crime he committed. Like how some stories mention that Satan was once an angel who was punished by God to being the lord of Hell after he tried to over throw God.
Considering that the maw is basically Warcrafts “hell” for us mortals. That does support this theory.
Wouldn’t be the first time blizzard has used the bible as inspriation. Look at the four horsemen in both version of Naxx and in legion. M’uru is basically purple Jesus who was willing to sacrifice his own life to allow a lost people (blood elves) to once again have a connection to the light. Thrall is Moses who led his people from oppression into salvation. The fact that Thrall was raised by humans like how Moses was raised by Egyptians helps supports this. Linking back to M’uru, Kael’thas is the false prophet who promises “paradise” but leads his people into serving Kil’jaeden (a character who was originally inspired by common imaginary of Satan). A’dal is God who forgives those who were once sinful but sought forgiveness, such as the scryers then the blood knights. Basically the blood elf plot from TBC is revelations mixed with the story of Jesus from the gospels.
Or, the Arbiter served the Jailer, and she betrayed him by allying herself with the Titans and jailing the Jailer. She seems like a very Order-y kind of being, and what with the relationship between Sargeras-Nathrezim-Helm of Domination-Torghast-Lich King-Kiljaeden-Maldraxxus, and between Ardenweald-Emerald Dream-Freya-Eonar, and Bastion-Kyrians-Archon-Valkyr-Eyir-Odyn, it doesn’t seem impossible.
That’s probably the earliest example of the trope, but you see it pop up a lot.
You saw it in the Matrix, where Agent Smith was tasked with suppressing the rebellion in the Matrix, but doing so meant he had to live among the humans he hated so much. So he basically broke the system in an effort to escape.
This was the goal of Hades in Disney’s Hercules and in the Clash of the Titans. He was tired of being stuck in the lame underworld and decided to break the system so he could become head of the pantheon instead.
It was the plot of Dogma. A couple of angels hated being on Earth among humanity (Hell to them) so much that they were willing to get back into Heaven on a technicality that might very well destroy all reality. And they were aided by a demon who had actually lived in Hell and would rather see them break the universe and destroy reality than continue living there.
In many a prison film, there’s usually a warden who dislikes the limitations of his position as just a Warden and seeks to elevate himself through illegal or unethical corruption/exploitation of the inmates whom he also resents. Often without the knowledge of his superiors.
We don’t even know if the guy is imprisoned as the chains appear to be aesthetic judging from the art so he might not be deposed but in full control over the Shadowlands!