A "stop-loss" is a decision rule that you can implement to limit how much money you can lose. Imagine you're Scopia in early 2011 - you've gone short Bekaert and the stock has gone up. You've taken considerable losses, but you're fairly certain that your analysis is correct and the market will eventually agree with you. What are the reasons you might want to hold on to Bekaert, and what are the reasons you might want to close out the short-sale and accept high losses?