Missing the Market's Best Days
There is no proven way to time the stock market. Periods of market volatility often lead to feelings of uncertainty and fear. When investors let their emotions drive their investment decisions, it can result in them pulling their money out of the market at the worst time, only to reinvest it later once things "turnaround". The problem with this reasoning is that it's impossible to predict exactly when the turning point will be, and the long-term impact of missing those first few days and/or weeks of growth can be significant.