Whenever you hear a discussion about the short-term swings in any given stock's price, your immediate thought should be whether it matters to why you are investing.

When it comes to investing, you are your own worst enemy.

If your investing approach requires that you become Nostradamus to succeed, then you are destined to fail.

You, your employer and your plan's investment managers fail to follow even the most basic rules of investing. You overtrade, chase performance, do not think long term. All of you - All Of You - have done a horrible job managing your retirement plans.

The beauty of diversification is it's about as close as you can get to a free lunch in investing.

If you are not making any mistakes, you are being excessively risk-averse. Investing involves risk, and that means you will occasionally be wrong. And although it is okay to be wrong, it is not okay to stay wrong.