[haphazardeous]

I wouldn't be that sure. Similar thing happened to me in the past. Two phone interviews (one with HR, one with a developer). Asked to go for a face-to-face and they asked me to do a coding exercise in an hour but what they wanted would've taken a good few days to implement.

Anyway, my solution worked. We went through my code and discussed a few possible performance improvements. I was also asked a few theoretical questions which I answered confidently and was under no pressure at all.

They got back to me two days later just saying 'no'. No feed-back whatsoever. It was because the two developer who interviewed me were the world's most miserable developers and the moment they walked in I could tell they have no interest in talking to me or interviewing me. Not even trying to engage in small talk. I wasn't going to take it even if I was offered the role because I wouldn't want to work with them. And they probably found me too friendly and sociable and instead wanted to work with an introvert.

Bottomline is it all comes down to the chemistry. This sounds like I'm talking about romantic relationships but it's more or less the same whenever you're about to join a new social group. That's why all these coding exercises, in my opinion, are just a waste of time.