Many retirees make the mistake of retiring without a plan for paid work. In this situation, even though you are retired, you need some type of income. A lot of retirees choose to work a part-time job for a financial cushion while other retirees use earned income. Earned income is especially important for people who would like to retire young. Did you know having income from a part-time job can delay social security claiming until you are at least 70 years old? Holding off on claiming social security can increase your final payout by as much as 8 percent each year.