Why have Warren Buffet and Charlie Munger been so successful in their investing? According to Munger, much of it stemmed from avoiding costly mistakes.

“It is remarkable how much long-term advantage people like us have gotten by trying to be consistently not stupid, instead of trying to be very intelligent.”

Rather than focus on being brilliant, they first made sure they were not making stupid errors—an approach that has done very well for them over the years. A stupid mistake can quickly erase the gains or momentum you’ve already experienced. It could cost you years of work, and your reputation. Making gains are exciting, but limiting your losses can be even more important.

Being aware of the mistakes you want to avoid, and taking steps to protect against them, has value in all areas of life—not just in investing and finance. Knowing the kind of person you don’t want to be, or the health issues you don’t want to develop, or the kinds of relationships you want to avoid, can bring awareness to the decisions and habits that could lead down these paths.

If you know where you don’t want to go, you can put up guardrails to protect you from going that direction. And this in turn will make it more likely you’ll actually head in the direction you do want to go.