> A nice feature would be, "negative points because". So that I can learn from it.

My hunch is that your comment was too short.

Thanks for your hunch. You have quite an impressive karma score considering your 68days old here.

Thankfully I enjoy this site for more than my karma record.

Does deleting it remove the lost karma?

Is the idea of negatively voting down a comment. ( Other than the obvious ) To encourage the user to delete it?

>Thanks for your hunch.

Actually I was being facetious. :)

> Does deleting it remove the lost karma?

Not that I can tell. My guess is that 'deleting' a comment actually sets a 'deleted' flag somewhere in the data base rather than actually removing it; but I haven't looked at the code so I'm just speculating.

> Is the idea of negatively voting down a comment ... To encourage the user to delete it?

No. The purpose is to encourage commentary that follows the site's discussion guidelines:

http://ycombinator.com/newsguidelines.html (see section titled "In Comments")

In fact, the window to delete a comment is only open for a set amount of time after posting, after which the site withdraws the option to delete.

Thanks for the link, the section you speak of gave me great insight.