Taiichi Ohno originally enumerated seven wastes (muda) and later added underutilized people as the eighth waste commonly found in physical production. The eight are: 1) overproduction ahead of demand; 2) waiting for the next process, worker, material or equipment; 3) unnecessary transport of materials (for example, between functional areas of facilities, or to or from a stockroom or warehouse); 4) over-processing of parts due to poor tool and product design; 5) inventories more than the absolute minimum; 6) unnecessary movement by employees during the course of their work (such as to look for parts, tools, prints or help); 7) production of defective parts; 8) under-utilization of employees’ brainpower, skills, experience and talents.