As with any futures trading, if a trade goes against you, you may lose more money than you initially invested. (With a stock or bond, your potential loss is limited to the amount you invested.) In fact, any significant move against your position before expiry could lead to a margin call for you to settle. Note that your brokerage may liquidate your position, without contacting you, to meet a margin call.
Under certain (rare) market conditions, you may also find it difficult—or impossible—to close out a position. This situation can occur, for example, when a market reaches a daily price fluctuation limit (limit-up or limit-down) or market circuit breaker.
In addition, stop orders on futures are not guaranteed an execution. Due to exchange rules based on certain conditions at the time of activation, the exchange may reject or substitute an exchange-designated limit order for the originally triggered market order.
Finally, while the nearly 24-hour trading in some products can be an advantage, it could also tempt traders and investors into making more trades than they can reasonably handle, creating the potential for larger losses. Futures trading is hard work and requires a substantial investment of time and energy. Studying charts, reading market commentary, staying on top of the news—it can be a lot for even the most seasoned trader.