When they finally arrived at Aqaba, Lawrence’s band of several hundred warriors killed or captured twelve hundred Turks, and lost only two men. The Turks simply did not think that their opponent would be mad enough to come at them from the desert. This was Lawrence’s great insight. David can beat Goliath by substituting effort for ability—and substituting effort for ability turns out to be a winning formula for underdogs in all walks of life, including little blond-haired girls on the basketball court.
— Annals of Innovation: How David Beats Goliath - Malcolm Gladwell
It’s important to note that this only works if you attack from the side!