In a lame man's language, greediness is defined as not being contended with what you already have, like for example, say you got something for free, and you are still wanting more of it for free, it means you are greedy, in crypto, if you invested in a coin, you already set your selling price which you already decided on how much profit is OK for you, fortunately, if you investment starts going up and hit your set selling price, you refuse to sell but rather set a higher selling price, and your investment ones again hit your second set selling price and again, you refuse to sell but rather, set another higher selling price thinking the coin will continue to go up, this simply means you are a greedy person and if you are not careful, you might end up even loosing part of the capital you invested in that coin.