I just saw a coworker who I hadn't seen in a while because she had retired. I asked why she came back and she said she and her husband can't afford to live on social security. Our company offers a pension, so she was getting that plus social security and they still couldn't make ends meet. I asked if she drew social security early and she said she retired at 72. We live in a very high cost of living area, but it makes me sick to think of people who live in a wealthy country working until they drop.
Edit: Sorry, I should have been more specific about why my coworker had to unretire. I was disgusted when I heard her story and when I posted and forgot to mention that she couldn't afford her health care(the most important part of the story). Apparently, the husband is disabled and their medications and health care costs drove her back into the work force.