The continued improvement of total quality management should be based on a circular system rather than a continuous single line because quality should not be thought of as having an ending. Treating it as a linear path does allow businesses to reach a specific goal, yet this stops them from continuing to search for places that need further improvement and thus prevents the creation of a new goal altogether.
When it is treated as a cycle the businesses will try to locate other faults and refine improvements because as one rotation ends another one begins. The cycle consists of stages. In sequence these are plan, do, check, and act. Shewhart first created this process in the early twentieth century and it held firm. It was revised by Deming from check to study, thus establishing its initials of PDSA.
Businesses using this cycle focus on productivity in the present and for the future using various diagrams, charts, and the like to plan, do, study, and act. Various diagrams include the activity network, affinity, cause and effect, matrix, scatter and tree diagrams and to a certain extent the interrelationships digraph.
Multiple charts of this nature include the control, flow, process decision program, Pareto, and run charts and the histogram. The prioritization matrix is another useful layout that businesses use to manage the quadrille cycle by organizing ideas into groups that may correspond to the relationships another similar item