In order to achieve customer satisfaction it is imperative to achieve customer specifications with greater reliability and accuracy. This in turns demands improvement in process capability and reduction in variations which can offset the production or service processes.
The basic concept of studying variation and using statistical signals to improve performance can be applied to any area. Such areas can be on the shop floor or in the office. Some examples are machines (performance characteristics), book keeping (error rates), and gross sales, waste analysis (scrap rates), computer systems (performance characteristics) and materials management (transit times). Until the processes, which generate the output become the focus of our efforts, the full power of these methods to improve quality, increase productivity and reduce cost cannot be realized.