It's not considered a repost unless it has already gotten attention recently. Things like time of day or day of the week or just randomness can affect if a post gets the discussion is deserves, so HN does allow reposts.
From the HN FAQ[1]:
> Are reposts ok?
> If a story has not had significant attention in the last year or so, a small number of reposts is ok. Otherwise we bury reposts as duplicates.
> Please don't delete and repost the same story. Deletion is for things that shouldn't have been submitted in the first place.
From the HN FAQ[1]:
> Are reposts ok?
> If a story has not had significant attention in the last year or so, a small number of reposts is ok. Otherwise we bury reposts as duplicates.
> Please don't delete and repost the same story. Deletion is for things that shouldn't have been submitted in the first place.
[1] https://news.ycombinator.com/newsfaq.html