Somebody on this very site quipped you can define a robot as "A machine that doesn't work yet," because if it worked you'd name it after what it does (like a dishwasher or a vacuum cleaner).
Most of the scenarios that I think to use the word robot, I can very easily conceive that its still underdeveloped and yet to be highly proficient at that task yet. Yet when it can, we will undoubtedly refine the term for that particular robot.
