[ColinWright]

All this is unofficial, but based on my own observations:

You can never down-vote a submission. When you have enough karma you can:

* Down-vote comments

* Flag comments

* Flag submissions

Flags on submissions affect their ranking in a manner similar to down-voting, except that enough flags can result in a submission being deleted entirely.

[dang]

Flags never delete a submission entirely. We don't delete submissions unless users ask us to (and have a good reason). Everything else remains visible with 'showdead' turned on in your profile.

[Artemis2]

I'd say that you might not have enough karma to have access to all the features.

[ColinWright]

Are you suggesting that with enough karma one can down-vote a submission? I certainly don't have enough karma yet.

[Artemis2]

Only Paul Graham knows.

[ColinWright]

Or any of the others who work on the code. However, even jacquesm[0] - third on the leader board[1] - says that to the best of his knowledge one cannot downvote articles:

    http://jacquesmattheij.com/The+Unofficial+HN+FAQ#downvotearticle

[0] https://news.ycombinator.com/user?id=jacquesm

[1] https://news.ycombinator.com/leaders

[dang]

There are no downvotes on stories, unless you consider flagging a kind of story downvote. That's a legitimate way to look at it, since it answers the complaint upthread [1]: if you think that a story is not appropriate for HN, that's what flagging is for.

1. https://news.ycombinator.com/item?id=8124546