Because the moment you stop doing the very things that got you to the top of the mountain is the very moment you begin the slid down to the valley.
What is this you call property? It cannot be the earth, for the land is our mother, nourishing all her children, beasts, birds, fish and all men. The woods, the streams, everything on it belongs to everybody and is for the use of all. How can one man say it belongs only to him?