for me stoplos is a function to help traders reduce the risk of loss, I personally always use it in every trade because I can't keep track of the development of my asset prices, I also have a busy life out there that I can't possibly leave, if you don't need it then it is a natural thing because maybe you are a person who has a lot of time monitoring price developments, so not everyone needs it but some people really need it
Without stoploss the loss is inevitable, a single slippery on the order book can melt the all balance faster than we click to the "close order" button on trading platform. Having an experience doesn't mean the trader should trade without stoploss because the market doesn't forgive such cases. A single news can cause a flash crash on charts which can lead to stop out.