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In Guardians of the Galaxy, if Thanos knew the orb contained an Infinity Stone (one of the most powerful artefacts in the galaxy), why did he send Ronan to retrieve it?
It was pretty clear from their short exchanges that Thanos and Ronan pretty much hated each other. Why would Thanos trust Ronan with such a hugely important task?
I know initially, Ronan didn't know that the orb contained an infinity stone, but Thanos was still taking a pretty big risk sending him to retrieve it.
Even with two of Thanos' daughters on board Ronan's ship, the orb would ultimately pass through Ronan's hands before it reached Thanos, so there was always the possibility he would discover it's contents.
Is there any reason established as to why Thanos doesn't go after the infinity stone personally?