Let's be realistic - absolutely everyone comes into trading to make money. And the overwhelming majority of them strive not just to satisfy their basic needs, but to gain full financial independence and prove it to themselves and others. And since trading is a potentially money profession, it is a very fertile ground for greed. You feel the opportunity to become very, extremely rich and it distorts your consciousness. I think any trader goes through this, at least there are a lot of articles about greed.
Hollywood movies about stock trading often surround the profession with a halo of romance and smooth out the sharp corners. Therefore, often in the minds of beginners, and sometimes quite experienced traders there is a change of concepts. They call greediness ambition or purposefulness, and their habit to break the rules because of it - adventurism. Indeed, all TV series like Billions or movies like the Wall Street Wolf show crazy traders who easily break all the rules and usually bring them results. However, reality is not a movie. In reality, greed is destructive.
The main problem is unrealistic expectations. Traders forget what risk and trade are and already mentally plan for success. Sometimes the reality is disappointing, but the trader was already so confident in success that he put all his eggs in one basket and remains with nothing.
The main cure against greed is a simple question 'Why I sure I will win?'. You should ask yourself that more often.