I think this function is a great tool that gives investors the opportunity to collect profits. Stoploss at the right time can help you overcome your greed to succeed. From what I know professional traders all use stoploss to minimize the risk when the market changes unexpectedly and make you fail to keep up.
Stop-loss is one strategy that could help for a safe play but still you need time and focus on our trades. But not all the time you'll be profitable when there is unexpected huge dump of prices. You can still be losing if you don't have time study flows and it's market chart, so therefore, you should always checkinh you trades every now and then.