Emotions could be a trader's worst enemy; they often lead to misjudgment and loss of a trade.
There's an old saying on Wall Street that "pigs get slaughtered." This greed in traders causes them to chase on the winning positions for too long, trying to get every last tick. This attribute is damaging to your trade plans as you are always running the risk of getting blown out of a position. Greed is not easy to beat because we always want to do better and try to achieve a little more. A trader should recognize this instinct and create trade plans based on rational decisions.
When your trades are in red, or bad news comes out about a certain stock or the general market, it's not unusual for fear to take the reign.
Sometimes we hold on to trades that we know are no good in fear of closing them and making the loss real. It's okay to have a loss and walk away. Sitting on bad trades just makes your losses larger and offsets any successful trading that you might be doing otherwise. If the trade isn't working out as expected, close it and move on.
Paralyse by Analyse
"Paralyse by Analyse" is an interesting phenomenon in which traders get so caught up in analysing everything about a potential trade, they never actually pull the trigger on the trade. In this case, what often happens is that the trader will constantly question all the minor details found in the analysis in an attempt to perfectly analyse a situation. This is a truly unachievable task, which can prevent a trader from both making monetary gains and achieving experiential gains by getting into the trade.
We are only human and, as such, perfection may not exist in trading. However, profitable trading can be achieved when emotional management is learned.