I'm willing to bet that short attention spans play a significant role in making karma less meaningful - in the sense that it can penalise more extensive and tho

I'm willing to bet that short attention spans play a significant role in making karma less meaningful - in the sense that it can penalise more extensive and thorough comments in favour of short, snappy one- or two-liners. Take the following scenario: you've got some interesting topic that most HN users will click on, and the #1 comment is like this: --------- parent comment line 1 --------- parent comment line 2 --------- parent comment line 3 ... --------- parent comment line x >>>>--------- reply comment line 1 >>>>--------- reply comment line 2 If you're in that jittery state of mind when you just want some infotainment without reading dozens of lines of dense and subtle text, isn't it more likely that you'll just read the reply to that top comment first, since it's short and snappy? It may even make you feel that you've made progress towards understanding what the parent comment was about, without actually spending the required amount of time on it. Topics on HN obviously have a strong bias towards solid intellectual content (and I don't necessarily mean academic topics), so it's probably unlikely that much insight can be gained from very short comments - unless the poster is particularly observant and skilled in condensing information, of course. That's just one of the reasons why I'm sceptical about karma. I think it does serve a purpose, but if the majority of users go into a topic with no real intention to read or comprehend anything thoroughly, karma becomes a less meaningful measure of contribution.