A discount with a deadline asks urgency to assist persuasion.

A time limit is not information about value; it is a way of preventing you from thinking. Given a week, most people would compare, check whether they wanted the thing at all, and often decide no. Given forty minutes, the question quietly changes from whether to buy into whether to miss out, and loss is a much stronger motivator than gain. Nothing about the product changed between those two versions of the question.

When a clock appears next to a price, treat it as a signal to slow down rather than speed up. Let one deadline pass on purpose and see how little you mind.