Something in the protoype stage is still a
prototype and has not yet reached
production.
In the protoype stage, it's all about gathering
data and gaining
experience so that the final product can be made, and made well.
A project that never actually reaches production stage, or that stays in the protoype stage for too long is said to be
vaporware.
If the prototype
tests certain
design assumptions, then it's a
POC.