If a person A asks a question which they understand to be on-topic, then later on some person B finds out that the question would have been off-topic if the asker A had prior knowledge that B now has, does that make a question off-topic, or does that mean that the answer is "Your understanding is flawed. The answer is not what you think: ."?
I'm asking about questions of the form:
On "StackExchange's 'Using Metal Detector's' Q&A Site" Q: I cannot figure my metal detector out; I'm pushing the button but it's not doing anything. It's a model ABC. How do I use it? A: The problem is not that you don't know how it works. Pushing the button would normally work, but the manufacturing company recently announced that metal detectors of model ABC were all broken in the factory but shipped anyway so all require service.
Is it more useful to leave an answer like above, or is it more useful to the community to leave a comment such as "it's broke, contact the company to have it fixed," down-voting the question, and giving the question a status of "put on hold as off-topic"?
Although there is a specific question of mine which prompted this meta-question, I care little for my question itself, especially since it did get an answer in the comments so I've been helped. I am asking hypothetically for future benefit to this community since this type of issue comes up frequently enough to be discussed.