this is a blind spot for many modern managers who are heavily influenced by the concept of the Pareto Principle, which observes that 80 percent of the leverage lies in 20 percent of problems. The dark side of the Pareto Principle is that we tend to focus excessively on the high payoff 20 percent. We overmanage this 20 percent, and undermanage the other 80 percent. This leads to what we might call the Pareto Paradox: There is usually more actual opportunity in the undermanaged 80 percent than the overmanaged 20 percent.
Donald G Reinertsen in The Principles of Product Development Flow