[dang]

It's just randomness, so perhaps not so strange.

The dupe detector only gets strict if a previous post has already had significant attention. It's more important to give good articles multiple cracks at the bat, than it is to prevent repeat URLs.

When we see cases where an earlier submission "loses", we sometimes look through that submitter's previous posts and see if there's another good article that we could invite a repost of. Those go into in the second-chance pool (https://news.ycombinator.com/pool, explained at https://news.ycombinator.com/item?id=26998308), so they get a random placement on HN's front page.