This paper investigates preemptive overcontrol exercised by a present-biased agent who is fully aware of her self-control problem. A usual understanding is that such an agent, a so-called sophisticate, performs a given task earlier than a time-consistent agent because she anticipates that even a single delay will cause her to complete the task beyond the ideal date. We first present a counterexample and provide a correct intuition by identifying the necessary conditions for preemptive overcontrol. We argue that a sophisticate would complete a task early when she anticipates that if she postpones, the net reward from completing the task will significantly decrease by the next task-completion date. Moreover, we show that if the net reward schedule is single-peaked, this intuition implies the usual understanding.