Some men give up their designs when they have almost reached the goal; while others, on the contrary, obtain a victory by exerting, at the last moment, more vigorous efforts than ever before.

Though widely attributed to Herodotus this in fact comes from the Histories of Polybius, Book 16, chapter 28: "Some men, like bad runners in the stadium, abandon their purposes when close to the goal; while it is at that particular point, more than at any other, that others secure the victory over their rivals". (Translation of Evelyn S Shuckburgh).