All 3D applications, whether it is a game or a learning VR-simulation, etc. require a suitable, immersive environment. 

Several tasks were, such as: Modelling, texturing, rigging, UV-Mapping, animating, and more, were required during the development process of the games and simulations I worked on, to achieve an optimal and satisfying result.

This covers all static background objects, that he player might never even notice, over vehicles the users might take to travel to the tools the users is using with their hands holding it right in front of their viewing position.

Another factor, the creation of 3D models is covering, is to determine the best level of detail of your models.  To achieve the suitible level for your application a correct  implementatin is esential to satisfy the necessary requirements such as: performance, quality and overall style, etc.