Regardless of the fact whether you need a small product or are well-informed about how your end product would actually be like, it is viable to have a prototype model at first place. Being an introductory version of software product that is being developed, it helps you proceed in a right direction while the product is in development phase.
Many of you often ask when would it be possible to see the first prototype of the project? Well, that depends on the methodology you choose to develop your product. Usually, Waterfall and Agile are the two most popular methodologies adopted for software development.
With waterfall approach, the development process is sequentially carried out as it flows down different steps. Once a phase is complete, it is impossible to go back to it in order to make changes. The only solution to cater to the need for modifications is starting everything from scratch. Thus, this model requires detailed documentation. The prototype model developed using this approach can be seen with tools in vision, but that would not be the actual product. However, you can always measure the results against the requirements and deliver feedback.
Conversely, when the Agile methodology is implemented, the entire project is segmented into small modules which are then worked upon, usually in weekly sprints. You can review the prototype at the end of each sprint and provide the developers with the feedback to improve the end product which can be implemented by the developing team right away.
No matter which product development methodology you choose, always make certain your team designs a prototype model first so that you can review it prior to original product build out in order to ensure any changes required are carried out on time, saving much of your efforts and cost.