The 80/20 Rule

Maybe studying just 20% of this curriculum will get you a high enough score. The pareto principle suggests that, in any given process, 80% of outcomes come from 20% of inputs. In a project, it implies 20% of the effort can lead to 80% of the results. Discuss with your team: are most people overworking most of the time?

Picture a hundred Italians and all the land beneath them: in Vilfredo Pareto's day, about twenty of them held four-fifths of it. Digging through tax rolls in the 1890s, he kept finding the same brutal split — a fifth owning most of everything — in country after country, almost no matter where he looked.

Key concepts

The Pareto Principle (80/20): The pattern that a small share of inputs produces most outputs — 20% of effort yields 80% of results, so where you put effort matters more than how much.
High-leverage Activity: The vital 20% that drives most results — finding it is the heart of working smart: identify the few tasks that move the needle and pour energy there instead of spreading thin.
Diminishing Returns: The flip side: the other 80% of effort produces only 20% of results, so beyond a point extra work yields little — knowing when you've captured the easy gains is part of using the rule.
The Critique: 80/20 is a rough pattern, not an iron law, and arguably more statistical coincidence than universal truth — misapplied, it justifies neglecting the unglamorous-but-essential 80% that prevents disaster.

What to know

01
If most of the output comes from a thin slice of the input, then effort and reward are misaligned by default — so 'just work harder' is often the wrong move, and hunting down the vital 20% beats grinding through the other 80%.

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