The single most expensive stock market trades are those made with emotions, but, of course, you are not an emotional trader are you?
Before you bought that stock, mutual fund or Exchange Traded Fund (ETF) you did your research to be sure that what you were buying would return a good profit over the long haul. You bought it and over time you look at it less and less.
Ask yourself: when you plunked down your hard earned money did you have any idea where you would sell it or where you might exit the trade should the stock go down instead of up? And suppose it has gone up have you made any plans to protect those profits?
There were many geniuses in 1999 who bought a tech stock at $20 and saw it run to $200 only to come back down to $2. Those who had an exit strategy probably sold out as it turned over and dropped like a rock. They kept most of their profits as well as their original investment.
What kept those BuyNholders in? It was emotion. They fell in love with the stock because they "knew" it was worth more and would "come back up".
Investing is not an "I hope, I hope" business, but it is a business. Never become emotionally attached to anything you buy. If you were in the buggy whip business in 1900 and saw the automobile putting the horse out to pasture you easily knew it was time to sell out. That also applies to any investment you make in the stock market.
Once each month you should be checking to see if your various stocks are advancing as planned. Forget all those pretty research reports your broker sent you. Burn them. Now you must not care anything about that company. What you care about now is your money. As long as the stock price is advancing you may continue your love affair, but when it starts down it is time for a divorce. Time to leave before the damage gets worse.
This is where emotion becomes expensive. If you just bought it your ties are strong and you know if you sell you will have a loss. Never fall for that old broker's adage that you don't have a loss until you sell. Anyone who believes that will be eating cat food at retirement.
When you bought that new car you knew as soon as you drove it off the lot it would be worth 20% less than you paid for it. Twenty percent is a lot and more than most folks should be willing to risk when investing. Forget "the long haul" as you don't want to take the 40% losses that many investors did in 2000.
Usually a good rule of thumb is 10%. When you drive that stock off the exchange floor your risk should be limited. You decide how much you are willing to lose if it goes down instead of up and as it goes up carry that risk percentage along to lock in your profit.
If you do sell never look back. Fagedaboudit! In 80% of those sales when you do look back six months later you will see you are way ahead in the money game.
Do not allow an emotional attachment to keep you in any stock or fund. It will drain you both mentally and financially.