Pareto Principle

Pareto Principle states that for many events roughly 80% of the effects come from 20% of the causes. Or 80% of results come from 20% of the actions or efforts.
It is also known as the "Law of the Vital Few" or the "Principle of Factor Sparsity"or the "80/20 Rule".

Management consultant Joseph M. Juran suggested the principle and named it after Italian economist Vilfredo Pareto, who noted the 20/20 connection.

This rule means that:
1. 80% of sales volume comes from 20% of products in the product line.
2. 80% of a company's revenue comes from 20% of its customers.
3. 80% of a company's production comes from 20% of its employees.
And on and on...

If you look at the activities that are completed during the day, you will find that the top 20% of your daily activities will result in 80% of the results that you achieve.
It is easy for general tasks to slip in and keep us distracted from the things that can move us forward in success, and many people find themselves slipping back into old habits of procrastination instead of focusing on the 20% that will propel you forward.

Pareto's principle keeps time management at the center stage by letting you focus on the most important tasks rather than spending time on tasks that ain't going to make much difference.

But be careful when using this idea! First, there's a common misapprehension that the numbers 20 and 80 must add to 100 - they don't!
20% of the workers could create 10% of the result, or 50%, or 80%, or 99%, or even 100%.

Remember that the 80/20 rule is a rough guide for typical distributions.

The key point is that most things in life (output, effort, reward) are not distributed evenly - some contribute more than others.