Nvidia, a member of the high-flying NYSE FANG+ index, reported third quarter results yesterday that missed estimates. The stock is down 19% this morning, and over 42% since October 1st.

Why have the shares cratered? Earnings are up 32% over the last year and the outlook remains positive with Goldman saying Nvidia โ€œhas access to one of the best growth opportunity sets in semis.โ€

The problem for Nvidia shareholders, in a word, was price. Early this year, Nvidia traded as high as 60X earnings. Investors buying shares at those levels were forgoing a necessary margin of safety. Without a margin of safety, even a small wave can sink your ship, as it did for Nvidia shareholders over the last month.