Why are yachts so expensive?

I'm curious, can you explain why yachts are priced so exorbitantly? Is it due to the intricate design and craftsmanship that goes into building them? Or perhaps it's the luxurious materials and high-end amenities that they offer? Additionally, I'm wondering if the maintenance and upkeep of these vessels also contributes significantly to their overall cost. I'd appreciate any insights you have on this topic.