While I don't agree with the other insepctor's response I can at least see his point. A buyer that asks that question is already 90% of the way to blaming the inspector for something. When I was newer I would also shy away from people with questions like that.

I would probably have answered by educating the buyer that most of the time people think we 'missed' something it was actually not visible at the time of the inspection. But, that when things are missed, it's a case by case basis and we will make things right if we truely 'missed' it.