The advantage of a stop order is you don't have to monitor on a daily basis how a stock is performing. This is especially handy when you are on vacation or in a situation that prevents you from watching your stocks for an extended period of time. The key is picking a stop-loss percentage that allows a stock to fluctuate day to day while preventing as much downside risk as possible. Setting a 5% stop loss on a stock that has a history of fluctuating 10% or more in a week is not the best strategy.