Originally Posted by jse
It would be really cool though if that one guy's supposition that circulated on the internet turned out to be true, that Thanos, being a master schemer that thinks 10 moves ahead of his adversaries really did intend to lose the Cube to the Avengers so that he could use it to teleport into Odin's Weapons Vault and snatch the Gauntlet. In that case, he can't really fault Loki, as Loki's loss would have been all part of the plan. However, that wouldn't really explain why Thanos would wait 3 year to enact the rest of his plan. You could also chalk up Thanos' knowledge of Loki's (and Thanos' own defeat) as "memories" of the future. Thanos, having gained omniscience and omnipresence at some point in his life, would some "memories" of a future that he technically hasn't lived through yet.
And Thanos being Thanos, he has a subconscious inferiority complex that makes him think that he is not worthy of his aspirations. Although he does always achieves goals that he sets before him, he also tends to lose the fruits of his labor soon after because he makes sure he surrounds himself with the means to his own downfall. Having Loki as the voice in his ear is not totally out of the question. I'm just saying it's not inconceivable for Thanos to keep Loki around. But yeah this is all conjecture to begin with. I think it's fun to play around with possibilities.
TL;DR: Thanos may have planned for Loki to lose the battle in TA so Thanos can gain a bigger prize (the IG). Thanos also has a known peculiar psychosis that causes him to surround himself with the means to his own defeat, and Loki can easily play a part in that.
....That "one guy's supposition that circulated on the Internet" that Thanos was deliberately letting Loki lose to maneuver the Cube into place for an infiltration of Odin's Treasury to nab the Gauntlet was me....
Also, agree with Smashlilman's post about Chthon.