80/20 rule

The Pareto principle (also known as the 80–20 rule, the law of the vital few, and the principle of factor sparsity) states that, for many events, roughly 80% of the effects come from 20% of the causes.


The 80/20 Rule Applied to Web Design


The Pareto Principle and Your User Experience Work

Interaction Design Foundation

Pareto Principle-Based User Research

UX Magazine

Using the Pareto Principle to improve your user experience

Keep It Usable

Applying The Pareto Principle To The User Experience

Measuring U