From the book "The Art of War" written by the great Chinese strategist Sun Tzu, some 2,500 years ago:
On Laying Plans
"It is a matter of life and death, a road either to safety or to ruin. Hence it is a subject of inquiry which can on no account be neglected."
On Waging War
"When you engage in actual fighting, if victory is long in coming, then men's weapons will grow dull and their ardor will be damped. If you lay siege to a town, you will exhaust your strength."