Final answer:
Reactive Merchandising is necessary when a presentation is no longer effective in driving sales due to inventory gaps.
Step-by-step explanation:
Reactive Merchandising is needed when a presentation is no longer impactful enough to drive sales due to breaks in inventory. It involves adapting the merchandising strategy in response to changes in the market or unexpected events. For example, if a popular item goes out of stock, a retailer might quickly introduce a similar product to meet customer demand and maintain sales.
Learn more about Reactive Merchandising