Almost any kind of object can be designed and simulated in 3D space. Starting with simple 1 component objects like cups or perfume bottles over multi component objects like jewellery to most complex machinery.

It is conceivable why offshore platforms and refineries, boats and ships or even jewellery are designed as a 3D simulation first. Volumes and costs can be predicted most precisely and problems usually occurring during the prototype phase can be avoided.

In short: 3D object design is the most economic way of product development available nowadays.