Vilfredo Pareto, the Italian economist spoke about the 80/20 principle. It specifies that 80% of consequences come from 20% of the causes. There is an unequal relationship between cause and consequence. The 20% is referred to as the 'vital few' and the 80% as the 'trivial many'.
Pareto's observation was initially in connection to population and wealth but it can be extended. Later on, he concluded that his observations were not limited to economics but also extended to other areas such as business, sports, and education.
In an exam, 80% of the paper is from the 20% of the syllabus. About 20% of your customers will account for the 80% of your revenue. 20% of the workforce will account for 80% of work done in the company. In a fundraiser, 20% of the donors contribute to 80% of the amount. 20% of a product's bug-tracker annoy 80% of the user-base. In sports, 20% of the players create 80% of the wins.
80/20 thinking is a way to achieve more from less. Start with celebrating excellence rather than trying to raise the average effort. Strive for excellence in a few things rather than being good-enough at many things.
There is a lot of wasted effort. The key is to understand which actions create the most impact. Stop worrying about the 80% that does not yield you any result and focus on the 20% that does. If you are able to successfully prioritise the 20% of the most important things, you will produce 80% of the results. The other 80% of effort yields diminishing returns and should be discarded.
Figure out the 20% in your life and the 80% will take care of itself