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Historic financial fails: The author of this article points to the performance of Greek stocks after 2008, which saw a decline greater than 95 percent in less than a decade. Before that, it was Spain who experienced from 1973 to 1983 high inflation, unemployment and slow growth that ultimately destroyed their capital markets. These instances are far worse than anything U.S. investors have experienced, but at present, some might say we’re in the midst of a market decline. While we might be, it’s important to keep in mind that this is natural. The market is a continuous cycle, and thankfully, it’s nowhere near 2008-Greek-stock-alarming.

Check your at-risk assets: So how do you avoid an investing market nightmare? Limit your exposure to individual markets and stocks, and diversify. Utilize income-producing assets that are less intertwined with traditional financial markets. Create a retirement plan that’s customized to you, your risk capacity and tolerance. And above all, make sure your retirement plan helps you avoid any and all investment nightmares.

My thoughts: It’s naïve to believe that just because the stock market has always gone up, it always will. Some quick research will uncover dozens of examples from economies around the world where this hasn’t been the case. In that light, diversifying your risk into alternative investments is crucial to avoiding a truly worst-case scenario, or "Investment Nightmare".