There are lots of rules to be a success trader and greedy plays a vital role.While trading never be greedy. If you become greedy while trading then you can be assured that there is 90% possibility to be a losser.
One must dedicate his/her time to be good when it comes to trading. At the point of this dedication, learning process is what happens, probably trading with demo account doesn't make you a professional traders until real assets are placed.
Greed is an effect of seeing means of carrying big bag filled with money, unaware of the deep pit up ahead. This can only be dealt with on a real life situation, cause everyone who is caught up in such situations wants to try it, thinking one can outsmart the market, not knowing it is greed that is playing it's way. Being greedy in the market is something every trader experience, just a few that can overcome the situation.
Experience in trading is what kills greed when in the market, it also create disciplinary quality to all professional traders, who is satisfied at his/her take profit position at all time, meaning him/her has learnt the principles of securing profits.
Trading deals with discipline, lack of discipline will lead to regrets. Trading is taking risk, it is important to take risk, a well analyzed and calculated risk is worth the taking, not the risk done out of excitement and desire for immediate acquisition of profits, which could be disastrous.