Karma is probably more closely related to how popular your opinion is on a given subject in the hacker news community. As you said it does not really encourage better writing, while there is sometimes a correlation between a good post and many upvotes, especially on very technical subjects.
Also, Karma on news submissions has become a race to be the first to publish the latest techcrunch news or related sites, so it's not all about comments or contents.
Also, Karma on news submissions has become a race to be the first to publish the latest techcrunch news or related sites, so it's not all about comments or contents.