We formally model the impact of presidential policymaking on the willingness of bureaucrats to exert effort and stay in the government. In the model, centralized policy initiative by the president demotivates policy-oriented bureaucrats and can impel them to quit rather than implicate themselves in presidentially imposed policies they dislike. Those most likely to quit are a range of moderate bureaucrats. More extreme bureaucrats may be willing to wait out an incumbent president in the hope of shaping future policy. As control of the White House alternates between ideologically opposed extreme presidents, policy-minded moderates depart from bureaucratic agencies leaving only policy extremists or poorly performing "slackers." The consequences for policy making are substantial. Despite these adverse consequences, presidents have strong incentives to engage in centralized policymaking.