The 80-20 rule is an aphorism which asserts that 80% of outcomes (or outputs) result from 20% of all causes (or inputs) for any given event. In business, a goal of the 80-20 rule is to identify inputs that are potentially the most productive and make them the priority
The Pareto Principle
https://www.nerdwallet.com/article/travel/baffled-points-miles-let-8020-rule-guide