Detective Pikachu

Why a Detective Pikachu box moves differently to a Detective Pikachu card

A card is worth what the card is worth. A box is worth whatever people think is still inside it, so a box price falls while Detective Pikachu is in print and starts climbing once it is not. That is why a two year old box can cost more than it did on release week, and why buying sealed at release is usually the worst moment.