Is this person going to be goddamn annoying to be around 40-45 hours a week? (Oh, how this has happened.)
Does this non-medical phd demand to be addressed as doctor? (Yes, this happened.)
Does he or she seem willing to do his or her share of the scut work?
Is he or she a failed academic who is getting an industry job and going to be a pain about it, or is this what he or she wants to do?
How much supervision does the candidate require? Initiative? If he or she runs out of work, is he or she going to to sit there and do fuck-all until I notice or will the candidate be proactive about getting more to do?
I understand some of our code is under tested, but unlike TDD wankery, there is a real business cost to spending a bunch of time writing tests and, since those systems are either mostly finished / slowly changing, or on their way out, is this candidate going to be difficult or suck it up and deal? (Yes, this happened. See also scut work and/or the realities of living in our fallen world.)
We've made a decision to standardize on scala/java and js/some frontend package I'm not sure of. I understand this isn't react or the new hotness; does this candidate seem like he or she will throw a fit then spend two months working on a service in a language nobody else uses (yes, this happened. And he was surprised when he was terminated. There were other issues but this was the proverbial straw.)
Hygiene. This should go without saying, but apparently I am cursed. If I can smell you in an interview, we're done. (And yes, this has happened.)
One more set of edits as the bad memories come back:
You look at my two female data scientists and a female engineering peer and the one female office manager and ask why there are so many secretaries working here? Yes, this happened.
You call one of my female directs "sweetie." Yes, this happened.
We're talking on the phone and you couldn't be arsed to spend 10 minutes on our site and come up with a 1-2 sentence summary of what the company does. You can be wrong, but you must demonstrate minimal interest. And to be clear about the level of detail: if I were airbnb and you said platform to allow people to rent out their homes for short stays, that would be awesome.