There were multiple interviews with short (15-minute) breaks in the middle. Most people asked a mix of technical and behavioral questions, but one of the interviewers did things a little differently.
After we briefly introduced ourselves, he immediately asked me a technical question. I usually talk through the problem and ask for clarifications, he mostly gave me non-answers. I was asked the same question by another company a week or two earlier, so I started writing out code on the whiteboard. At a few points I asked whether or not I should handle an edge case, and every single time he said "yes".
When I was done writing all of the code, it took up pretty much the entire board. He asked me - "Why do you have so much code on the board?" and I responded "because I'm handling a lot of edge cases". As I recall that was pretty much the end of the interview.
I'm generally pretty good at interviewing, so I took whatever he threw at me and just thought he was a little off. It's not hard to imagine someone who isn't great at interviewing or has imposter syndrome doing worse in that interview just because of the way the interviewer acted.