risk and return

Picture two ways to use $1,000 for a year. One is a government savings bond that will almost certainly pay back $1,030 — safe and dull. The other is shares in a young company that might return $1,500 or might return nothing. Why would anyone touch the risky one? Only because it offers the chance of a bigger reward. This trade-off — you generally cannot get higher expected returns without accepting more risk — is one of the deepest truths in finance.

Return is what you earn, usually as a percentage of what you invested. Risk, in finance, means uncertainty about that return: not just the chance of losing money, but how widely the outcome could swing around its average. A safe asset has a narrow, predictable range; a risky one has a wide range with real chance of loss. Because most people dislike uncertainty (they are risk-averse), they will only hold riskier assets if compensated with a higher expected return. That extra expected return demanded for bearing risk is the risk premium — for example, shares historically returning several percent a year more than safe bonds, on average, to pay investors for the rollercoaster.

This principle organizes the whole investing world into a ladder: cash and government bills at the safe, low-return bottom; government and corporate bonds in the middle; shares, property, and start-ups toward the riskier, higher-expected-return top. It is also the test for spotting nonsense: any pitch promising high returns with no risk is either a misunderstanding or a fraud. The crucial word, though, is expected. A higher risk premium is the average reward over many bets and long horizons; on any single risky investment, the whole point is that you might still lose — the higher return is a probability, never a promise.