What is Mastery? Mastery comes with deliberete practice. This type of practice is geared towards repitition with an eye on increasing proficiency, confidence and competence. Typically specific tasks are practice and then combined with other tasks to exhibit more complex skills.
It is not the quantity of practice that is important but rather the quality. Now don’t get me wrong, you have to put in the required time and the right effort to master anything complex. But, short focused practice is the way to achieve mastery over time. Please watch the youtube video above for a description of what I mean.