[octokatt]

Ideally, interviews should be a chance for both parties to learn something. Normally, this is learning about the position/ whether the position is a good fit.

In abnormal cases where it's clear the interview progress will go no further, hopefully both parties can learn more about something else. Technical domains, career progression tips, even different strategies for tackling a problem (just because your method is not going to work in the company doesn't mean hearing about it for ten minutes won't help).

That said, if there's a major mismatch between interview and resume, ask if there's outside factors. Maybe they just found out their dad is dying and were trying to tough it out through an interview. Maybe they're autistic and should have asked for an accommodation because they're fighting through a florescent-light-fueled-migraine. Once or twice that's been the case, and giving them a second chance on a different day was the right call.