The elements and principles of art are the same for painting, sculpture and design.  I like sculpture because I have a certain kind of understanding of it.  I like to observe the action and balance of figures and the emotion in faces.  Clay is so responsive to the slightest pressure.  Its easy to use, but it has its drawbacks.

Clay is heavy, it cracks and explodes and slumps.  It's impossible to use for large figures, so I started using papier mache in order to create size.  It requires engineering for balance, and it easily has instant mass and color.