It was a question of the form trying to figure out how you deal with "X", and he denied X having ever happened, despite that being a core part of his current role.
He was an internal candidate, we were interviewing him to see if we could trust him with more responsibility (more X specifically), since the new role shouldn't cover up X when it happens. The role involved doing X for himself AND for other people.
Similar to the form of "tell me about your biggest weakness" and you responding with "I have no weakness".
I guess it's a bit different when it's an internal candidate.
I've been on the recieving end of clueless folk trying to make me feel small when I've just been looking for a job, so I might be a bit sensitive about it! Sorry for any offense given. Thankfully I'm beyond that craziness now and can just do what I want for work.
instead of telling him out loud, "hey we see you're hedging and applying bullshit interview speak, your answer isn't sufficient", we asking in increasingly obvious but different ways.
It was an internal candidate so it would be awkward to tell him to his face he was floundering.