The 80/20 is based on the principle that 80% of results are produced by 20% of the effort. This comes into play in many circumstances, such as marketing, sales and productivity.
i.e. Most of the work you do may actually be the result of only 20% of your time, the rest you’re procrastinating etc.
Scott H Young has extended this idea into almost all facets of life including relationships, time-management and internet usage. Is there merit using the 80/20 rule as much as possible?
Budget - Calculate all your discretionary expenses (after taxes, food and necessities). Now compare the money value of each expense with the utility of the purchase. If you wanted to compare different entertainment items in your budget, you could value each expense on the pleasure it brought you. If you wanted to compare different investments or tools you could compare return rates or productivity gained.
What it all comes down to is evaluating the worth of anything. It’s just handy to have a rule to work with.
Twenty Unique Ways to Use the 80/20 Rule Today - [ScottHYoung]
Also see: Pareto’s Principle: The 80-20 Rule – [NotesToSelf]