Warren Buffett Investing Lecture 2001 | Don't look into the rearview mirror

The past tells us that the market can be erratic. Years can go by with the market not growing at all. The country can do well, but the stock market itself doesn't necessarily have to follow.

You have to detach yourself from the headlines and what others are saying, and focus on what you know. Whether it be a certain industry or company, it's best you stay in your ever-growing circle of competence.