Many people start bottom-fishing with the idea that "it has already fallen a lot," testing the waters with a small position. But as long as it keeps falling, they keep averaging down, for a very simple reason—the lower it goes, the cheaper it gets. The result is, they keep adding to their position all the way down, quickly maxing out their position halfway down the mountain. Once it continues to fall further, they completely lose any room to maneuver, and can only watch helplessly as their account shrinks. They can't average down to reduce the cost basis, nor are they willing to cut their losses, ultimately becoming passive.