This is a topic that will get everyone talking, and one that I have struggled with over the years. Many will say you are foolish to trade without a stop loss but there is research out there showing how a stop loss placed below your entry point will hurt your accounts performance. Here is a link from Author/trader Thomas Bulkowski where he has done research to show how stops will hurt your account.
For myself I have seen far to many trades trigger a stop order ( sometimes to the exact pip or penny if trading stocks) lock in a loss and reverse back into profit ground. To avoid this I have experimented with alternatives to Stop orders, one is a mental stop, often this is a red line on my chart that I must have the discipline of manually closing the position if price falls below and reminds there at day’s end. Still another way to protect your account is with position size. On a 1K lot, price would have to move against you 1000 pips to loose $100,
One place I do like to use stop orders is protecting profits when I have a winning trade, I like to let my winners run, and having a trailing stop in place when I am away from my computer will keep that winning trade from turning into a looser