Finite agents such as human beings have reasoning and updating processes that are extended in time; consequently, there is always some lag between the point at which we gain new reasons and the point at which our attitudes have fully responded to those reasons. This phenomenon, which I call rational delay, poses a threat to the most common ways of formulating rational requirements on our attitudes, which do not allow rational beings to exhibit such delay. In this paper, I show first how this problem undermines synchronic formulations of rational norms. Then I show how it likewise undermines the most natural diachronic modifications of these norms. Ultimately, I argue that a successful account of rational delay will reject norms that directly govern attitudes or states of mind like belief and intention altogether, in favor of norms that fundamentally concern temporally extended rational processes like deliberation.