It illustrates the importance of creating a well diversified and thought out investment strategy that suits your individual risk profile. Many people are arguing that it's a great time to have your money invested in cash considering the volatility in the markets vs. the high interest rates you are getting on term deposits and cash. In the short term this is probably quite a good strategy.
However research clearly shows us that cash is the lowest performing asset class over time. The challenge comes when you take you money out of cash, as there is an opportunity cost of holding cash over the long term in the form of a lower return. Research also shows us that missing the best days of performance in the sharemarket can significantly lower our return.
So the issue then becomes one of timing. In my experience and numerous studies I have seen, have clearly shown that the majority of people are pretty lousy at market timing. Therefore there is a strong argument that unless you are an expert in a particular investment field you are probably better off with a well structured and diversified approach to your investing.