The additive manufacturing (AM) industry is now almost 40 years old, yet severe problems still persist in yield, accuracy and efficiency. Hard-won breakthroughs in physics, chemistry and engineering have developed prescriptions for the motion of mechatronics, and the dispensing of the materials, the ideal temperature and humidity of processes and machines should follow these equations exactly. Everything, in theory, should turn out perfect, but this is not always the case in practice. Out of a batch of one dozen parts that are 3D-printed, maybe only seven, eight or nine meet structural and functional standards, based on my experience. Additive manufacturing technology is very, very good, but it has not yet fully matured.