People, even smart people sometimes fall for the myth that everything a computer outputs is correct, so as developers we have an obligation to do our very best to ensure that computers always output the correct data.
The only correct answer is not to play the game. Or something like that. Joshua taught me that.
If the question is being asked is deterministic, then yes we have an obligation to make sure that the answer is correct. However so many things in life are either non-deterministic, deterministic but seemingly infinitely large state space, or deterministic but with nearly infinite number of inputs to essentially make it non-deterministic. What are we to do in those cases where there is no correct answer but only probable ones?