United Income estimates households miss on an average of $110,000 from claiming Social Security at the wrong time, usually, from claiming too early. Why are so many Americans claiming Social Security too early? Of course, Americans without much in retirement savings may feel like they have no other choice, but the fact that many Americans underestimate their longevity may be another important cause. A simple mathematical concept called “conditional probability” helps explain why this happens. My article explaining “conditional probability” was named a Forbes.com Editor’s Pick.