If quantum programs are encoded through quantum bits, and those qubits exist as a superposition of values, by necesity the program must be in a superposition of running and non-running states.
Also it's important to note that while in a classical sense, the program never actually ran on the data, in a quantum mechanical sense it was enough to flirt with the possibility that the program might run for an answer to be obtained.
As for full-time quantum physicist, part time comedian Onur Hosten's "A non-running computer produces fewer errors" comment: Note that you can still have quantum errors from a non-running computer, as long as the possibility exists that it can run. For truly error-free operation though, nothing beats classical computers. An old server I have in my work room has not generated a single error ever since I went at it with a massive sledgehammer a few times. I expect it will remain error-free for the foreseeable future.
