re: Question to the HR people, interviewed

I'm not pissed that they didn't hire me (maybe a little) but my question is really, in such group interviews anyone who doesn't like something said or rubbed slightly the wrong way gets veto power?
I've never been in an interview where I got such good feedback and even at the end of the interview it still felt like I was being convinced to "join the team".
So is this SOP for hiring, is it likely that I rubbed 1person the wrong way.
Since they did not hire me and they did not discuss anything about clinical ability, was it purely personal? Didn't like my clothes or something?
Interviewing is such a dog and pony show anyway.
The only place that I did hiring, an HR person did an initial and I did the second and final interview.
What is the purpose of group interviews from managerial standpoint?
Just wanting a different POV for why what happened, happened.