A voodoo priest can foretell the future by tossing bones, sticks and other objects on the ground and interpreting their alignment.
An automation engineer can predict how parts will behave in a vibratory feeder bowl by dropping a handful on a table and analyzing their positions. Engineers can’t be sure what a part will do, especially under vibration, without knowing its center of gravity, and they can’t tell that from a drawing. One way to find that out is to drop the parts on a tabletop and look at their natural orientations.