Some believe that they can trade 24/7, maybe some can. But for the vast majority of us we need to be at our premium state of mind. Like a sport you need to prepare yourself, your mind and body to perform at optimum levels when we're in the game.
We are driven and manipulated by our emotional state, the key is not to try and control your emotions, but to understand how they work for you. When you're completely focused, your trading strategies, with education will be easy, you'll hit the target time after time.
If you trade without considering how outside influences may affect your performance, you may end up trading blind, when you trade like this your discipline and strategies have taken second place, now your trading for the thrill, and it's more psychologically rewarding when you are successful, but you miss more often, and slowly watch your account dwindle. Because there is a greater 'reward' when making a successful trade without thinking, the mind is prone to trade this way, because it's the easy way out.
When your focused and your able to trade by function of your strategy, the psychological reward is lesser, although your success is likely to be greater. This is because the mind associates risk reward, the higher the risk in the action, the greater the psychological reward for success, you get a big injection of serotonin, and it's attractive. It's harder work with less reward to trade with premeditated skill and technique, in fact a successful trade may yield little reward when your so sure of success that there is no mental risk reward aspect.