My Dumbest Investment

I worked for a company, had a lot of stock options and bought stock as part of the company plan. I was a millionaire on paper for a while and greatly believed in the company, not believing it could go bankrupt. I didn't sell my options when I should have, and I lost everything. I learned that sales don't necessarily make the company. At fool.com I learned to look at the fundamentals. If I'd done that earlier, I'd have seen my employer's pile of long-term debt and no cash reserves to survive a downturn. I'm very grateful for the lessons learned. I've changed my focus from trying to get rich to working on being happy. I found a new employer that supported good health. I ran marathons, and now, at 53, I enjoy triathlons. That's worth more than what I would have made on my stock options.

- Iain G. Kelly, San Mateo, Calif.

The Fool Responds: As you learned, it's dangerous to have too many of your eggs in one basket, even if the basket looks very sturdy.

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