This paper argues that preparation over time is a ubiquitous cognitive capacity in various degrees depending on when critical events occur. Experiment 1 investigated the way humans differ in their predictions concerning the modulation of the sequential effects and the results have shown that duration is an important factor in interpreting time. Particularly, the impact of duration is central on the arousal level due to sequentially fast preparation processes. Moreover, experiment 2 tested whether the results of experiment 1 could be generalized to a simple RT-context. Participants were asked to self-evaluate their subjective state along four dimensions: variations in motivation, attention, boredom, and fatigue. In overall, the results suggested that there are different processes underlying these dimensions, supporting the dual-process account.