I will often pick something "expert" on their resume to dig into, if nothing else than to gauge what "expert" means to them. Recently I interviewed someone who

I will often pick something "expert" on their resume to dig into, if nothing else than to gauge what "expert" means to them. Recently I interviewed someone who emphasized databases on their resume, and later mentioned they were very highly skilled in that area, so we started talking about indexes. I think I asked something like "Why wouldn't we just put an index on every field?" and the best I could get from them was "it might speed up, it might slow down" but they couldn't articulate why. Another one I will sometimes ask: You're an expert in language / framework x and have been using it for 10+ years? Cool. What recent additions have you most excited about it? What things about it do you hate/disagree with the most? Not being able to answer these things don't mean you 'fail' the interview of course, but to me it's a strong signal that our definitions of "expert" are different, and so I'll make that assumption about everything else on your resume.