When Jim Cramer first started out in trading, he didn't like rules. He believed that either they couldn't really help, or they would cut his upside and prevent him from making more money.
After getting burned too many times, he learned the value of discipline.
"The rules protect you against your own bad judgment about what's going on at the companies you own or what's happening in the market overall," the "Mad Money" host said.
In order to really make money in the market these days, investors need discipline. Mistakes can cost you in trading, but if you do nothing with your money, you will have a whole lot of nothing to show for it.
Cramer constantly worries about the stocks in his charitable trust. He sees danger when the stocks in his portfolio go down as the market goes up. That tells him that someone knows something he doesn't.