But then two things happened. First, Kevin and Maciej had the good-faith conversation described at https://news.ycombinator.com/item?id=11441978, and Kevin reluctantly concluded that Maciej doesn’t want to participate in the program as intended. I don't know the details and can't speak for Kevin, but that's his call to make as the partner who runs YCF, and I know he hoped and expected it to go the other way. Getting into a YC batch isn't a cash prize—it's a close working relationship, and that's something that has to be right on both sides or it won't work. Both Kevin and I wanted it to work (if we hadn't, we'd simply have dropped Pinboard from the runoff and said why), and I felt sure that a good-faith conversation would be enough to bridge any remaining gap. It turned not to be, which is disappointing.
Second, we found evidence of vote brigading, something we'd disqualify others for. I don't believe that Maciej organized a voting ring (actually I don't believe he'd give it a second's thought), but when we dug into the data we found that the votes for Pinboard look dramatically different from the votes for the other startups. I presume this is the effect of Pinboard's (deservedly) large audience being asked to promote the post, e.g. at https://twitter.com/Pinboard/status/727255170594131968 and https://twitter.com/Pinboard/status/719599297604390912. We didn't know about those links earlier; we only found out about them from user complaints after the runoff was posted. But we would and did disqualify people for soliciting votes on a small scale, so it wouldn't be right to allow soliciting them on a large one.
We're sad about this. As I said, Kevin and I both really wanted it to work--I thought it would be good for HN and Kevin admires Pinboard. We also appreciate that humor and irony and "a variety of publicity stunts" (https://news.ycombinator.com/item?id=11443463) are Maciej's style, and he was simply practicing it. That part is not a problem--as readers, we enjoy it too, and creative cleverness has always been prized on HN. I both take Maciej at his word that he wasn't trolling and Kevin at his word that he tried to find a way to accept Pinboard into YCF and in the end just couldn't.
We're going to have a community discussion about things that didn't go so well with this first Apply HN experiment, but I'm not sure I'd put this in that category. I'm glad that we chose to believe the serious parts of what Maciej posted. I think it was the right call, I still believe them, and under similar circumstances would do the same again. It's not always easy to tell the joking bits apart from the serious bits, but that goes with the territory.