Greed is greed. It is not good and it is not bad. But it is necessary to contall your greed.
It is very important to stop in time. If you do not stop when you are investing it is possible to lost a lot of money.
But because of greed it is very difficult to stop in time and continue to investing or speculation on the market.

It is impossible to control your greed because if you control your greed it means that there is no greed at all.
If there is a real greed it is imporssible to control it. It is impossible to contral real greed.
Thanks greed people always want more and more. And can not stop in their desire.