As up trends end, the same crowd that lifts price provides fuel for the ensuing decline. Longs get lulled into a false sense of confidence as rally momentum fades and a topping pattern forms. Seeking to protect profits, they start dumping the stock.
Price fails and selling spirals downward through wave after wave.
Common pattern features appear in most price declines. Several false bottoms print and fail. Volume surges repeatedly, as losers unload their positions onto the waiting value crowd. Price carries well past downside target after target. Then just as hope collapses, the stock makes a final, multiple bottom.