Or you made the person feel insecure, you were poorly understood in the 45 minutes they had to talk to you in between meetings and a hard problem they were wor

Or you made the person feel insecure, you were poorly understood in the 45 minutes they had to talk to you in between meetings and a hard problem they were working on, you didn't have the right clever data structure shibboleth that their Cs 101 course taught, etc etc. There are a lot of reasons you can fail the culture fit. Doesn't mean you aren't the problem, but as someone frequently interviewing candidates I can tell you blame also rests on the other side of the table.