Right at the start, the finish for a model or a prototype will not be the same, as the two objects are made for a different purpose.
A model is the representation of an object; it is designed to be tested and validated for the sake of detecting any faults, but also to be improved. It is not necessarily life-size. Whereas a prototype possesses all the technical qualities and all the operating characteristics of a new product. Its functionality and feasibility are ensured.