Why did Odin and Thanos part ways with such powerful artifacts?

This is a mind-bender: Why did Odin leave the Tesseract on Earth, when he actually had the Infinity Gauntlet in his vault? The All-Father must have known what it was and he must have wanted to keep it safe. Just like the Casket of Ancient Winters, he must have known that the Tesseract could bring ultimate destruction if left in the wrong hands.

And yet, he left it on Earth.

There is also another, even bigger question: Why did Thanos hand the scepter to Loki in the first place? He surely knew that it contained one of the Infinity Stones. And if he tries to collect all of them, it just doesn’t make sense.

Of course, we don’t really know what the Mad Titan’s plan is, and maybe that is why it doesn’t make sense right at this moment. But even if it will be explained later on that he wanted the Avengers out of his way, it will still sound ridiculous.

Just like it sounds ridiculous for him to send Ronan to collect the Orb, when he could have done it himself (What, is the MCU going to show us that this was also part of a plan, since Thanos didn’t want a direct confrontation with the Nova Corps?!?).

Speaking of Infinity Gauntlets…