The 80/20 Principle asserts that there is an inbuilt imbalance between inputs and outputs, causes and consequences, and effort and result. It states that a minority of causes, inputs or effort usually lead to a majority of the result, outputs or rewards. A few things are important; most are not.
The 80/20 Principle involves a static breakdown of causes at any one time, as opposite to change over time. "The art of using the 80/20 Principle is to identify which way the grain of reality is currently running and exploit that as much as possible," advises Richard Koch.