The 40-70 Rule

Colin Powell's 40-70 rule captures something important about deciding under uncertainty: do not wait for 100% of the information before you act. Below about 40%, you are guessing. Past about 70%, you have likely waited too long and the opportunity is slipping away.

The rule sounds rough, but it carries the core probabilistic insight: certainty is expensive, and past a point, more information costs more than it adds. The best decision-makers are comfortable acting on partial information, because the alternative — waiting for certainty — is usually a worse decision in disguise.