I am in the middle of reading this book, which says that great performances in any field have more to do with "deliberate practice" than with talent. We tend to believe that prodigies, like Mozart and Tiger Woods, have innate talent that is well beyond that of others in their field.
In truth, these two both had fathers who were determined to train them to excel in their fields. Early performances from either one would be considered ordinary, but their constant training and honing of their skills led each of them to extraordinary heights of mastery.
How can I use this information in painting? I have bemoaned the lack of inspiration during dry periods. During these periods, I can hone specific skills. In other words, I can do painting exercises designed to improve areas of weakness, and maintain areas of strength. I have plenty of books which suggest specific exercises for just that sort of thing.
Classically, artists have used the copy method of gaining skill. That is just what athletes and musicians do, and it is valid. To repeat what someone else has created gives the eyes and hands the experience they need; then variations on a theme can be developed, to enter into an expanded endeavor.
Painting teachers gave us exercises, yes, but the impression I had was that those exercises were for beginners, and that once one had the skills, one simply came up with one's own projects. That is not quite the way it works. Exercises accumulate experience in a specific field, and though it takes many hours to develop any one skill, it is built upon, hour after hour. Though I am learning this lesson late in life, it can still improve my work.