The most difficult thing in our life is to winning over the mind and keeping it in the control.
For example, if you want to achieve something in your life and day and night you are working very hard to achieve your goal, at some point there would come a desire in your mind to hang out with your friends or watching your favourite web series. If at that point, you are able to control over your desire and keep yourself engaged in the work then you have won over these desires and nothing can stop you to achieve your goal.
Power of words 