Of all great works, nine-tenths must be drudgery. Edison put it at 99%. Edmund Burke worked 22 hours at one stretch on one speech … pure drudgery.
Kepler filled 600 pages with figures to learn the skies – all drudgery. Genius and talents may start great projects, but only drudgery can finish them
Russell Conwell
Nothing in the world can take the place of persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination are omnipotent.
Calvin Coolidge