Definition:

1. There is an inbuilt imbalance between causes and results, inputs and outputs, and effort and reward.

References:

1. Vilfredo Pareto, 1897 discovered the patterns underlying the 80/20 Rule, or Pareto Principle. Found that the majority of income and wealth in 19th century England went to a minority of people.
2. George K. Zipf in 1949 discovered the "Principle of Least Effort", that around 20 percent of a resource accounted for 80 percent of the activity related to that resource.
3. Joseph Moses Juran, 1951, the Quality Control Handbook described how the 80/20 principle could be applied to industry to root out quality faults and improve reliability by focusing on a vital few variables.
4. In 1963 IBM discovered that 80 percent of a computer's time is spent executing about 20 percent of the operating code.

Insights:

1. A minority of causes, inputs, or effort produces a majority of results, outputs, or rewards. Equally the majority have little impact.
2. You can use the 80/20 Principle in life to become happier by focusing on what matters.
3. Businesses can use the 80/20 Principle to become more profitable by focusing on the most valuable customers or products.
4. Complexity is costly.
5. A few things are always much more important than most things.
6. Progress means moving resources from low value to high value uses.
7. Big wins start small.
8. The majority of achievement and happiness takes place in 20 percent of our time.
9. A few key decisions have the biggest impact on our lives.
10. We are much more productive at some things than others.
11. Time management assumes we know what is and is not a good use of time, but using the 80/20 rule, this is not a good assumption.

Principles:

1. Look for short cuts.
2. Strive for simplicity.
3. Use the least possible effort for maximum results.
4. Be selective.
5. Strive for excellence in few things, rather than good performance in many.
6. Delegate to specialists where possible.
7. Only do what you enjoy the most and best at doing.
8. Only play the games where winning matters.
9. Eliminate low value activities.