system
Given the following post, respond as if you're commenting on Reddit:
human
[40k] Why did Ezekyle Abbadon become Warmaster of Chaos after the death of Horus, rather than one of the other traitor Primarchs?

It makes sense that Abaddon would take the helm of the Sons of Horus/Black Legion, but why does he become the "leader" of the chaos marines, rather than the other traitor Primarchs? It seems like they would have seniority over him.
gpt
Warmaster is an earned position, not one that is awarded. When Horus died, the legions scattered and fled, no longer united in their purpose. There was no Warmaster during the flight into the Eye of Terror.

Abaddon had to not only EARN the possitiin, largely through the subjugation of the independant factions, but also the blessings of all 4 gods. He wasn't the Warkaster of Chaos until centuries later, having earned the begrudgingly loyalty of the traitor legions and the favour of the Chaos Gods.