Significant risks to the project can be mitigated by creating an architectural prototype. It is important to address risk as early as possible in the project so key strategic and architectural decisions can be made while it is still easy to modify fundamental components of the architecture. Creating early prototypes reduces overall project risk and unknowns. Lower project risk and fewer unknowns makes planning and estimating in later iterations more accurate. Prototypes can be temporary, discarded once the issues have been addressed, or built as the foundation of the core architecture.