When Warren Buffet and Bill Gates were asked about the single most important thing for success, they both answered 'focus'.
I started to realize how important focus is when I play basketball. This all comes from my personal experience. Often when I play, if I get distracted by different thoughts in my head, I feel lost. My reaction time slows down, my body feels stiff and heavy, and time passes unconsciously. It seems that my body is not listening to my mind.
The skill level between players may be the most dominant factor, but whether the player is focused or not, it is still significant.
As Michael Jordan once said, as much as it is about physical sports, it is also a mind game.
The same is true for life. If you are focused enough, the chance that you will achieve something is greatly enhanced. That's why self-help books often advise you to write down your goals and read them every day. Remind yourself that these are important things to you and you should shield yourself from all other distractions.
This will spur an upward spiral. When you become more focused, you become more motivated to achieve your goals as you start to see success. When you see success, you know your strategy works, and you will keep pushing yourself forward.
So the conclusion? Let go of your assorted thoughts that may distract you, ruthlessly prioritize the important things in your life, be laser-focused, and constantly reward yourself for minor achievements to ensure you are on an upward spiral.