Because he wouldn't stick to one thing and follow through, Leonardo da Vinci, one of the most admired artists of all time, will never be considered the greatest.
We all treasure the Mona Lisa (it was the one painting I most wanted to see). He also painted The Last Supper, although in his lifetime it began to peel.
Da Vinci produced countless other unfinished masterpieces, countless inventions which were never put into play, and countless unpublished works.
Though da Vinci was a great man, because he flitted like a butterfly from one project to the next, he achieved a small fraction of his God-given talent. Even he would agree. One of his last journal entries reads, "It is not a good thing to attempt the impossible."
Da Vinci is one of the reasons I am such a proponent of sticking with things for the long haul. Better to finish a few things well than to start a lot of things which never quite get completed.
On the other hand, Michelangelo, of the same era, possibly is the greatest painter--and sculptor--who ever lived.
During a family trip we were able to stare at the ceiling of the Sistine Chapel, the wall of The Last Judgment, and gaze reverently at the Pieta in the Vatican City. In Florence we were we inspired by the statue of David.
There is Michelangelo, and then there is everyone else. He reached his full potential of service to mankind because he was a finisher, not just a starter.
Until every church disciples every man...