I like to see these remnants from when most folks made their living farming. They may have outlived their original purpose and their continued existence may due to having been pressed into service for general storage, or simply because they aren't in the way.
They appear in endless variety.
Sometimes you can guess their original purpose from design. This one may have been a corn crib.
Others don't offer any clues.
Has this one been cannibalized, or was just it a shelter?