I thought it was over, but now it is back: customer reactions to ex post time extensions of sales promotions

In many industries, it is common practice to extend sales promotions ex post. That is, firms belatedly extend the initial deadline of a promotion shortly before or directly after the previously announced deadline, with the expectation of increased sales. Four experimental studies indicate both positive and negative effects of these ex post extensions. First, customers perceive an ex post extended promotional offer as less attractive, such that their repurchase intentions diminish. This negative effect arises consistently across different boundary conditions, such as different customer and product types. Second, the positive effect of ex post extensions stems from the possibility that the consumer can still use the promotional offer, so it emerges only for potential customers and existing customers of frequently bought products. Companies can mitigate the dark side of ex post extensions proactively, by designing the extensions to last for only a short time or offering an explanation for the extension that highlights the popularity of the initial promotion.