From The Wall Street Journal
The world we live in asks us to make an abundance of financial decisions every day. These range from the inane, such as whether to risk a parking ticket when you stop for one minute to drop off your dry-cleaning; to the highly complex, such as which funds and investment products to pick for your retirement savings.
All of these decisions require risk-return tradeoffs. Unfortunately, while people have many opportunities in life to perfect their strategy concerning parking tickets, the same is not true for the complex and all-important decisions of how to invest retirement savings. By the time you learn whether a retirement strategy was the right choice, it is usually too late to change it.