I interviews around a bit this summer. I found one position that, on paper, I was the perfect candidate. I ticked every checkbox the hiring manager mentioned. I met with the hiring manager first, and she loved me and by the end of the meeting was insisting that I come into the office for an onsite with her team. A few days later, I went into the onsite and nailed it. I mean, there were zero indications that I had flopped. By the end of the day, the hiring manager came in, smiling and asked me the good stuff about salary expectations, when i could start, etc. All good responses.

Then she said that since this is a senior position, we'd have to run it by the CTO, who was based across the country. They decided to do a Skype interview. As soon as the screen came up, I got a sinking feeling in my stomach. The CTO was relatively hostile and didn't smile throughout the whole session, even when I cracked a joke that never fails to get a response. By the end, she gave a terse "Thanks for your time" and that was it.

I didn't get the job.

But this is one of those things where I really believe I put my best foot forward, and I really believe that I was a great fit for that job, and I really believe that there was some other factor completely, 100% beyond my control that caused me not to get the job. Maybe she already had someone in mind. Maybe she was having a bad day. Maybe I had something stuck in my teeth, or maybe someone close to her died. Who knows?

I'm still really bummed I didn't get that job, but at the end of the day, it is what it is, and I have to move forward.

Good luck with your next interview, OP. It'll work out eventually. :)