The 6 biggest investing mistakes

The stockbroker's real job is not to make money for you but to make money from you. Brokers tend to be friendly for one major reason: It gets them more business. The typical broker "talks to" about 75 customers who collectively invest about $40 million. (Think for a moment about how many friends you have and how much time it takes you to develop each of those friendships.) Depending on the deal he has with his firm, your broker gets about 40% of the commissions you pay.

So if he wants a $100,000 income, he needs to gross $250,000 in commissions charged to customers. Now do the math. If he needs to make $200,000, he'll need to gross $500,000. That means he needs to take that money from you and each of his other customers. Your money goes from your pocket to his pocket. That's why being "friends" with a stockbroker can be so expensive. A broker has one priority: getting you to take action, any action.

We urge you not to engage in "gin rummy" behavior. Don't jump from stock to stock or from fund to fund as if you were selecting and discarding cards in a game. You'll run up your commission costs - and probably add to your tax bill as well.

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