Why are the cherubim placed “east” of the Garden in Gen 3:24?

This is not clear. If the cherubim are placed eastward, it would follow that they were blocking Adam’s way, meaning that he had been expelled in that direction. Throughout the Bible, the east, or things “eastward,” are often associated with corruption and curse: this is where Assyria and Babylon were, and where the Israelites were exiled. Cain, too, was exiled east of Eden in “the land of Nod,” after killing Abel (Gen 4:15). This might serve to explain why some of the earliest, most ancient people came from the southeast of Mesopotamia.