The craft of leadership is a skill just like every other skill there is and it must be learned like all those others as well.  While we may absorb some knowledge and even some rudimentary skills from observing others and watching how they lead (good and bad) it isn't until that we are thrust into leading others that our leadership learning is really tested.  But like other skills, leadership skill must be practiced, deliberately and deeply.  K. Anders Ericsson would suggest that it takes about 10 000 hours of deliberate practice to develop deep and meaningful skill.  From a leadership perspective one should ask themselves how are they developing the expertise in leadership that they need and how can they get their 10 000 in over a quicker time frame?  A key answer is through reading, videos, seminars, webinars and conferences.  These are all great ways to supplement your "on the job" training in leadership, enhance your pattern recognition, and provide you with a broader skill set to become a better leader.

If you only rely on your "on the job" training in leadership to become a better leader, you will likely be sorely disappointed and delayed in reaching any appreciable skill level.  This is primarily due to the fact that most leaders don't lead all day long.  When you think about the time that a leader is actually leading their team it is actually a fairly small percentage of the time throughout the day.  Meetings don't always count towards the total nor does doing some paperwork or desk work.  In fact, the total time in a day / week spent actually doing "leadership" type work might be as  low as 20%-30%, or lower. which means it could take 15 years or more to gain any appreciated expertise in leadership solely from your on the job type training.  And then when you think that often our weekly, monthly and annual cycles of processes are simple repeats of the same skills, one's leadership skills inventory may be even more severely limited after the 15 years.

If you want to be a leader you cannot simply leave your development to fate or to what you may learn in the role.  You must become deliberate about your training and your skill development.  Not only do you deserve to be the best leader you can be, those you serve need you to be the best as well.

Live as if you were to die tomorrow. Learn as if you were to live forever. Mahatma Gandhi

For the things we have to learn before we can do them, we learn by doing them. Aristotle

Success has to do with deliberate practice. Practice must be focused, determined, and in an environment where there's feedback.  Malcolm Gladwell