User blog comment:Ynwa244/Unstable Star/@comment-84391-20120508194306

It was related to Drew K's original vision for the Reapers: Dark energy periodically builds up, eventually causing entropy and decay. The star would've been a sign of this. An ancient alien species (I think a leaked script called them the Zateri) saw this coming, and altered themselves into a form that would enable them to stop it, resulting in the first Reaper. It was only able to temporarily forestall the heat death, so the Cycles occurred everytime buildup got critical. The Conduit, and Sovereign's death, threw them off their game, and harvesting humans was supposed to be their "final saving throw."

Once this was thrown out the window, that star became a hanging chad.

A similar thing happened with Star Trek once; the neural parasites in the TNG episode "Conspiracy" was supposed to be the first wave of an insectoid species that eventualy evolved into the Borg. Insectoids proved too expensive, so they replaced them with cyborgs, and the parasites were forgotten despite the episode's ending.