Personally I have my limits for the number of bets I play within a time frame. After 3 bets, I most likely back off even if I'm winning or losing. You are right when you mentioned that people get greedy and keep Betting when they win bets, making them lose at the end most times. Let's remove greed from the picture and know our limits.
Indeed. Emotions can make you reckless on the bigger winning or losing streaks. The same for the bet sizes, people tend to raise there bets to battle losses but most of the time it wont play out.
That's because it will never increase their chance of winning when they adjust their best.
What's only important is to predict the outcome and has to be right most of the time, experts do understands that, that's why they have good bankroll management and they set a decent funds so they can also monitor their progress in whatever gambling type they are into.