So how or why is it paper beads are made with different shapes? It ALL lies in the shape of the paper. There are 5 shapes on the left. The 1st shape is the traditional paper bead. The remaining 4 are the variations you will need to cut the paper in order to make a bead of the respective shape. Inventing and playing around with paper shapes will give you beads of all size and shapes.
These are some of my own inventions of various shapes ;)