Would You Sell Your House if Its Price Dropped 10% in a Day?
Some investors have a habit of checking their stocks every day. I do it too. And I read up on my stocks all the time. If I see a big price move, I check the headlines and try to figure out the reason behind it. I want my stocks to go up, and I don't want them to go down.
The pace of some of these price moves can be very quick. If you're an investor like me, it's not unusual to see some growth stocks have 10%-plus price swings over the course of a single day. These quick changes can spark emotions. A price jump can get me excited, maybe even a little greedy. If the news is bad or the stock price drops, I might get upset, or possibly even fearful.
These attitude changes are natural. But if you let them get the best of you, they can lead to investing mistakes, the worst being "buying high and selling low." That's not good.
Source Fool.com