It would be great if Social Security covered all of your retirement expenses, but sadly, that's not the case -- and it's not a mistake. Social Security was never supposed to be your only source of retirement income. It was initially part of a "three-legged stool" that included personal savings and a pension. As pensions have become less common, workers have had to increasingly rely on personal savings. How much you need to save is a largely individual question, but understanding how far your Social Secur ...