They never should have been given an origin
Here's the inherent problem with that: people wanted an origin. People demanded an origin. It's why people who care about the Halo series were pissed when Halo 3 came around and offered no explanation of what the Forerunners are.
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TheRock ~ Slow dramatic zoom-pan. Doesn't phase the hooded man.
"You have issues." - MWC. Pot. Kettle.