This paper formally models the virtues of Edmund Burke's conservatism, characterizes the optimal level of conservatism, and applies the model to management, law, and policy.  I begin by introducing ``switcher's curse,'' a trap in which a decision maker systematically switches too often. Decision makers suffer from switcher's curse if they forget the reason that they maintained incumbent policies in the past and if they naively compare rival and incumbent policies with no bias for incumbent policies.   Conservatism emerges as a heuristic to avoid switcher's curse. The longer a process or policy has been in place, the more conservative one should be.  On the other hand, the more conservative were past decision makers, the more progressive one should be today.