The difference between the wise and the foolish virgins was not a difference in knowledge but a difference in character.
The difference between Alexander's little army and the tremendous army of Darius was not so much in numbers as in preparedness.

Trained under Philip of Macedon for many years, organized for conquest and aggression, prepared to meet any situation that might arise, Philip's army carried Philip's son from victory to victory, and made him the master of the world.

Caesar was great in peace as well as war, but it was by Caesar's army that Caesar's greatness was established; and it was a thoroughness of preparation unknown before that made Caesar's army great.

Napoleon's successes were built on the splendid preparation of a mind transcendently fitted to grasp both principles and details, and on the comparatively unprepared state of his opponents.
The Great Elector began in 1640 a course of laborious and scientific preparation which committed all Prussia, as well as the army, to acquiring what now we call "efficiency." As this plan developed, especially under the Elector's grandson King Frederick William, the next King found himself, as Alexander had done, the chief of an army more highly prepared for war than any other.

By means of that army he made himself Frederick the Great, and raised Prussia from a minor position to the first rank of European Powers.