The vast majority of human lifts that start from a belt or cramped shelf - in sorting, loading, and last mile. Humans will sometimes rotate the box to center th

The vast majority of human lifts that start from a belt or cramped shelf - in sorting, loading, and last mile. Humans will sometimes rotate the box to center the load over an edge or regrasp from the bottom - but any given box is definitely going to experience moments with no support from the bottom.