A principle that the critical few, about 20% of items such as assets, failures, parts etc., should receive attention before the insignificant many, usually about 80%. This principle is named after 19th century economist Vifredo Pareto, who suggested that most effects come from relatively few causes. That is, 80% of the effects come from 20% of the possible causes. Synonymous with the 80/20 rule.

Tip excerpted from: The Professional's Guide To Maintenance And Reliability