CG models can be used for many things from adding interesting elements to videos or animations. STL models can be used for 3d printing or CNC machines. Create an endless supply of assets for video games, apps or AR/VR worlds.
Creating your own models can save time and money on your projects and be easily changed without needing to re-shoot live photos.
Show customer or potential clients a representation of what their final product will look like in a real world setting before adding manufacturing costs and prototype production.