Somehow we equate the amount of time we've been doing something to the quality with which we do it. Longevity does not equal competence. I am confident we could all think of someone who has been doing their job for a very long time, and might not be the best at it.
I worked with an actor recently and we discussed the routine of practicing the craft. We talked about singing, and acting; and then the discussion turned to actors who have been working for a very long time, but some didn't seem to develop past a certain point. Simply performing for decades doesn't grant mastery over the craft if there is no discipline and routine.
I could practice a piece of music for three hours with focused determination on solving the areas where I am having difficulty. Or I could simply play through the piece for six hours, and keep struggling over the same spots, but never bother to focus on them. Likewise simply singing through the full song, or running the full scene doesn't address the problems in the performance.
Just because we put in the time does not mean we are using the time effectively. And when was the last time we had time to waste? Knowing how to effectively diagnose the areas you need to work on will not only save you time, but the hours spent practicing will actually count toward a better result.
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