"programmers like neat little boxes, and especially boxes within boxes within boxes. For some reason. Regular human beings on the other hand, tend to think linearly, which is why the Windows explorer for example has tried in a few different ways to flatten the file system hierarchy for the user."<p>Regular people think in terme of boxes-inside-boxes as well. They'll know, for example, that the dog food is kept in a sealed plastic container in the bottom drawer of the leftmost cupboard in the kitchen. That's a four level hierarchy, just for the dog food. Same goes for books, clothes, the vacuum cleaner, the band-aids - hell, pretty much everything.<p>Hierarchies are how we keep information sets small and manageable. Removing that does not simplify things; it's more like just lumping everything you own into a big pile on the floor and searching through hundreds of items every time you need something.