The main reason why prototypes exist is that we need to narrow down the risk of making something that doesn't work. Imagine that you have infinite time and resources; what would be the point of creating a prototype? Why not just create the entire game, and if it doesn't work, we'd have all we need to try again? Prototypes exist exactly because we need to make the best use of the scarce time and resources we've got.
When we build a prototype for a game, we're generally looking at:
- Whether a mechanic is engaging
- Selecting the best idea from a set of alternatives
- Testing the technical feasibility of an idea (where the idea can be anything from a full game to a graphics technique or AI algorithm)
- If the user can navigate the ...
