Generally, investors are concerned with the risk of major losses, known as Left Tail risk. This name comes from the concept of distribution of returns, in which the full range of potential returns from an investment or market over a period of time sort of looks like a “bell curve”. The far left side of that curve, or the Left Tail, represents large-scale losses that statistically occur infrequently.
Yet investors must be aware of another type of risk—the risk of missing out when the market delivers large-scale returns represented on the far right side of the return distribution curve. This “missing out” is known as Right Tail risk.