Traders, Defend Against the Dreaded Death Spiral.
It has often been said that there is only two ways to get hurt really bad on a stock trade, getting caught in a "death spiral" by not using DTM: Decisive Trade Management in the way of stop loses and having a stock halted on you. Halts you have zero control over. Death spirals are of your own making if you do not practice the use of stop loses.
It is my firm belief that capital preservation is one of, if not the single most important thing a trader has to concentrate on. It is also my belief that it is always better to error on the side of safety or caution, in general this all comes under DTM: Decisive Trade Management.
Stop loses and the discipline to use them are part of DTM
As a personal guide, in a market with very tight trading ranges, I'd think twice before letting a sock turn down by 50 cents or so. That is a very tight stop loss for the most part; again this can be flexible depending on your knowledge of the stock and its trading habits coupled with your own tolerance for loss. On an $85 stock, 50 cents is not all that much, but on a $9-10 stock it's a much larger percentage. Markets trading in tight ranges and lacking volatility make it much more difficult to recover loses if the follow through is just not there. If the average profit in a trade is 25-75 cents, then letting one get down on you a buck or more is going to wipe out most if not all of the previous gains on two or three plays. It can take that many trades to get back to even.
On the other hand some stocks can move $2 or $3 in a heart beat and reverse just as quickly for $2 or $3 move into the money for a total of $4-$6 or more. A $.50 stop on these will have you stopped of the trade and out of the money more often then not. I suggest that unless you are familiar with these stocks that have a history of wild swings that you avoid them until you get familiar with them.
The Trading Stop Itself
It is the opinion of many experienced traders and one that I share, that the stop order should not actually be placed. Instead you determine what price it should be and be ready to place the order if and when the trade turns against you and nears your stop price. This is referred to as "mental stops". You can even go as far as having the order form all filled out and ready to execute as the price approaches your stop price. A lot of the newer trading platforms will allow you to actually place the order in their system but it is not sent to the market for execution until the price is reached.
When you actually place the order, you lose control of you trade. Many systems do not allow you to have two orders on the same position at the same time. If you want to sell the stock you first have to cancel the stop and get confirmation back before you can place another order.
On a stock that is moving rapidly against you some traders prefer to use a market order for the quick exit. I do not like the use of market orders any under circumstances. There are too many pitfalls involved with the use of market orders. Instead I suggest you use a limit price that is significantly lower then the bid that assures you get a fill.
However you chose to exercise the use of stop loss orders is up to you but it has to be done. DTM with the use of stop orders is the only way to defend against the dreaded death spiral.