A man with definite aims to be accomplished may be compared to one digging a well. To dig the well to the depth of seventy-two cubits and stop without reachin the spring is, after all, throwing away the well.
Notes from Wikiquote
Compare | Oh, Soul, remember howe’er small the scope
Of thought or action that around thee lies,
It is the finished task alone can ope
The gates of paradise. — Anon.