system
Given the following post, respond as if you're commenting on Reddit:
human
[MCU] How did the Tesseract end up on Earth in the first place?

It was under lock\-and\-key by this seemingly religious order, and there's some connections to Norse mythology there.

This implies that the Asgardians, who've defended Earth from time to time, were at least aware of its existence. So why leave it on Earth and not in Odin's treasure room? Did an Asgardian just lose it, and did they not have the knowledge or technology to find it again? If they left it by choice, why would it be safer with a less advanced civilization than guarded by some of the most powerful beings in the galaxy?
gpt
I believe they mention that Odin left it there for safe keeping. He thought a quiet out of the way planet like Earth would be a good place to hide it. It seems he was right, since it remained on Earth until another Asgardian came for it.

Presumably he wasn't aware that humans already possessed the Time Stone (or they didn't get it until later) or he wouldn't have, since the Asgardians seemed to consider keeping two infinity stones in the same place to be pretty risky.