As long as no one is hit everything is successful, but as soon as a few men are wounded, the difficulties begin.
 Winston Churchill, The Story of the Malakand Field Force (1898). copy citation

Context

“I had the opportunity of witnessing six of these retirements from the rear companies. Five were fortunate and one was disastrous, but all were attended with loss, and as experienced officers have informed me, with danger. As long as no one is hit everything is successful, but as soon as a few men are wounded, the difficulties begin. No sooner has a point been left—a knoll, a patch of corn, some rocks, or any other incident of ground—than it is seized by the enemy. With their excellent rifles, they kill or wound two or three of the retiring company, whose somewhat close formation makes them a good mark.” source