There are a few investment managers, of course, who are very good - though in the short run, it's difficult to determine whether a great record is due to luck or talent. Most advisors, however, are far better at generating high fees than they are at generating high returns. In truth, their core competence is salesmanship. Rather than listen to their siren songs, investors - large and small - should instead read Jack Bogle's The Little Book of Common Sense Investing.