Honestly a lot of the greed based decisions have probably held people back. What I mean is that for the most part if someone wins big, then loses a game or 2 they start chasing. That will kill off any profit quicker than anything else. Take the loss and move on. I do it all the time and know it while in the middle of betting and still can't stop.
Greed is always the worst enemy when it comes to gambling. Many people who lose money in a game often have the belief that they can recover their losses by playing more. However, they often end up losing even more money in the end. On the other hand, those who win a huge amount of money but continue playing without cashing out can also experience regret due to their greed.
Personally, I don't gamble so often but when I sense that luck is not on my side, I choose to quit quickly to prevent further losses.