That's the basis for "conservatism": recognize that many processes, rules, barriers, morals, norms, etc. have been hard-won and hard-learned at great cost (money, lives, time), that we may not remember/understand quite why they're in place but they're there for good reason nonetheless, and abandoning/destroying them out of ignorance may doom generations to suffer until they re-discover why those were enacted in the first place.
That's also why rebuilding systems from scratch (the old "just rip it all out and do it again") usually doesn't work: there is a great deal of wisdom, however poorly implemented or documented, buried within that system. Starting over abandons those minute but critical bits, and must be re-discovered the hard way.
And yet the crowning achievement of conservatism in the last thirty years has been tearing down the processes, rules, barriers, morals, norms, etc. that were put in place during the Great Depression to prevent capitalism from tearing itself apart again.
Actually, although I don't agree with the idea, this is part of a conservative process. What is supposed to be conserved is the established order (Rich over poor, work over lazyness, God over men, etc.). The premise is that order has value, even if unfair, and that an established order is better than no order at all.
It is the blessing, and the curse, of culture that generations have suffered to find a balanced set of behaviors and rules. Change them at your peril! Its kind of like a system of natural selection - societies must be conservative to survive long-term. Rules change over generations, variations are few since the survival of the collective depends on (some of )them.
However, the world and the society we live in is changing so quickly (technology, cultural mixing, global warming, you name it) that the new norm for changing the rules is not generations but years or months. Using Facebook? Change your settings today or lose your entire life history to strangers! and so on.
That's also why rebuilding systems from scratch (the old "just rip it all out and do it again") usually doesn't work: there is a great deal of wisdom, however poorly implemented or documented, buried within that system. Starting over abandons those minute but critical bits, and must be re-discovered the hard way.