No it's not wrong, it's important. Too many believers are afraid of admitting that hypothetical though, as if merely countenancing it would make it true.
There should always be some doubt as to claim 100% certainty would just be bearing false witness. Nobody is 100% certain.
What you're talking about is honest inquiry, which many believers don't do. It may strengthen or weaken one's faith depending on their moral backbone. Some people are interested in what is true, and some are not.