The Deming Plan-Do-Check-Act Cycle
"W. Edwards Deming in the 1950's proposed that business processes should be analyzed and measured to identify sources of variations that cause products to deviate from customer requirements. He recommended that business processes be placed in a continuous feedback loop so that managers can identify and change the parts of the process that need improvements. As a teacher, Deming created a (rather oversimplified) diagram to illustrate this continuous process, commonly known as the PDCA cycle for Plan, Do, Check, Act*:
PLAN: Design or revise business process components to improve results
DO: Implement the plan and measure its performance
CHECK: Assess the measurements and report the results to decision makers
ACT: Decide on changes needed to improve the process "
Read more in this balanced scorecard article.