You begin digging down, looking for solid footing and then the process begins one more time. Once again over a long period of time the wall grows to the six foot height and then collapses. Despair and depression begin to haunt you. Instantly you're wide awake, visions of all the crumbled walls race across the landscape of your mind. The question that has bound you with depression and despair has been answered.
Perfection reproduces perfection.
The converse must also be true, flawed people build flawed walls. It's eternally impossible to build a structure greater than the builder. For Millenniums, man has been trying to build the heavenly Taj Mahal. We have developed powerful computers and sophisticated technology which we have married to social and political engineering. All our wonders can muster is a six foot wall.