Lesson 15: Risk and Return

Every investment carries a trade-off that never goes away: to earn a higher return — the money an investment makes — you must accept higher risk, the chance of losing money or earning less than expected. A savings account is low risk and low return: your money is safe, but it grows slowly. Shares are higher risk and potentially higher return: they can grow fast, but they can also fall sharply. There is no investment that is both perfectly safe and highly rewarding; anyone who promises one is either mistaken or dishonest. Understanding this trade-off is the key to making sensible decisions about money for the rest of your life.

Risk comes in many forms. The price of a share can fall because its company has a bad year, or because the whole market falls. Inflation is a risk to savers: money in a low-interest account can lose buying power over time. Lending money carries the risk that the borrower does not repay. Even keeping cash at home is risky — it can be stolen, and it earns nothing while prices rise. The point is not to avoid risk entirely, which is impossible, but to choose risks you understand, and to take only as much risk as your goals and your time horizon require. A person saving for a goal next year should take very little risk; a person saving for thirty years from now can afford to accept the ups and downs of the market, because there is time to recover from falls.

Diversification: Not Putting All Eggs in One Basket

The most important tool for managing risk is diversification: spreading money across many different investments, so that a bad result in one is balanced by better results in others. A single company's share can fall to almost nothing if the company fails; a fund holding hundreds of companies will barely notice one failure. Diversification does not remove risk — if the whole market falls, a diversified portfolio falls too — but it removes the risk of a single bad choice ruining everything. It is the reason funds exist, and the reason sensible investors never bet everything on one share, one company or one country.

Time Horizon and Patience

The second tool is time. Over a single year, share prices are unpredictable and often fall. Over twenty or thirty years, they have historically tended to rise, though past results never guarantee future ones. That is why the length of time before you need the money — your time horizon — matters so much: a long horizon lets you ride out falls and benefit from recoveries, while a short horizon forces you to sell at whatever price the market offers that day. Patience is therefore not just a virtue in investing; it is a strategy. The investors who do worst are usually those who buy in excitement when prices are high and sell in panic when prices are low. A plan made calmly in advance, and followed through the ups and downs, beats reacting to every headline.