Question for sellers

I’m a buyer and want to understand something from you sellers. I buy just about everything for life from Amazon and often utilize the warehouse. Occasionally, I have returns as well. On two return occasions, Amazon has notified me that they will need to inspect the item to refund. What triggers this notification? Is it a type of item that is often swapped out or is it something I’ve done? Just curious. One was AirPods (refunded after inspection) and the other is a clarinet reed. Thanks.