I recently remembered something that happened when I was being interviewed for my current job, back in 2004: I think three different interviewers all asked me the same technical question. I don't remember offhand what the question was, but let's say it was something about functional programming.
I came away from the interviews convinced that the company was weirdly obsessed with functional programming. If they didn't care a whole lot about it, then why would they have asked about it repeatedly? It must be one of their most important concerns.
Months later, after being hired and learning how interviewing worked at this company, I figured out that it had been pure coincidence. There was a list of suggested questions to ask, and three of the interviewers just happened to pick the same question from the list, and although there was sort of a process in place to avoid repeating questions, that process didn't work very well.
I kinda feel like this is just one instance of a larger point: as with the practice of rejectomancy, it's very easy to over-interpret when trying to understand why interviewers are doing what they're doing.
Another example: For a long time, one of my standard questions when I was interviewing tech writer candidates was about how they deal with difficult engineers. Eventually I noticed that I kept feeling the need to explicitly note that that's not actually a problem that I run into much around here. And I realized that asking that question was probably leading candidates to assume that there were a lot of difficult engineers around and that we needed to make sure they could handle that. So I stopped asking about it.
(Written in October 2015, but not posted 'til now.)