As a result, when surprises occur – for example, the Fed signals an earlier-than-expected exit from zero interest rates, oil prices spike, or eurozone growth starts to pick up – the re-rating of stocks and especially bonds can be abrupt and dramatic: everyone caught in the same crowded trades needs to get out fast. Herding in the opposite direction occurs, but, because many investments are in illiquid funds and the traditional market makers who smoothed volatility are nowhere to be found, the sellers are forced into fire sales.
结果，当冲击发生时——比如美联储放出信号将比预期更早退出零利率政策、油价上涨，或欧元区增长开始复苏——股票以及（尤其是）债券的价值重估将来得突然而猛烈：困在同一种拥挤式交易的所有人都需要快速退出。反向羊群效应由此产生，但是，由于许多投资困在了低流动性基金中，而平滑波动的传统做市商又不见了踪影，卖家将被迫挂出跳楼价。