“Risk means more things can happen than will happen.” ~ Elroy Dimson.
Warren Buffett likes to say that the first rule of investing is “Don’t lose money,” and the second rule is, “Never forget the first rule.”
Read any literature from any legendary investor, and “avoiding permanent loss” or “avoiding risk” emerges as the primary factor that has helped him or her become successful, and legendary.
Howard Marks writes in The Most Important Thing…
Investing consists of exactly one thing: dealing with the future. And because none of us can know the future with certainty, risk is inescapable. Thus, dealing with risk is an essential— I think the essential — element in investing.
It’s not hard to find investments that might go up. If you can find enough of these, you’ll have moved in the right direction. But you’re unlikely to succeed for long if you haven’t dealt explicitly with risk.
The first step consists of understanding it. The second step is recognizing when it’s high. The critical final step is controlling it.