Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

When to sell a stock?
My theory is that for every stock you buy, you should have an exit strategy and follow it.  It is too hard to let emotions rule if you let your default strategy be "let's see what happens." and emotional investing will almost never serve you well.  So before buying a stock, set a maximum loss and maximum gain that you will watch for on the stock, and when it hits that number sell.  At the very least, when it hits one of your numbers, consciously make a decision that you are effectively buying it again at the current price if you decide to stay in. When you do this, set a new high and low price and repeat the above strategy.