All of us have gone through that phase when we are still a newbie so there is no need to be ashamed about that but we must be proud to tell this story on how we overcome it later on. Even if most of us are successful now, this kind of stories will still be a very big part of us. In your case there you said you only sell your coins for 2x and 3x profits?
I think that was still fine and not totally disappointing at all. What is really disappointing is if we ended up in a loss because of chasing higher returns. Like the title says, excessive greed is detrimental to success so that means that a non-excessive greed is still fine as it gives us unnatural energy.
Moderate greed is the same as an investment that is very risky but still has good control even though it almost got stuck. If you only pursue high returns without thinking about the risks that will occur, all profits and even capital will also be lost. It is not good to trade too much, there must be good management and at what limit to stop. If you overdo it and get too greedy it is just like gambling, there will be no results in the end.