Gamification is great, but from personal experience I find it only works when I'm already engaged. e.g. I'm interested in what's going on HN and the karma point

Gamification is great, but from personal experience I find it only works when I'm already engaged. e.g. I'm interested in what's going on HN and the karma points help motivate me to contribute, or get a sense of whether my comments are valuable to the community etc. Same with StackOverflow etc. Gamification won't convince me to do something I'm not already interested in doing, and to some extent, even things I would like to do (e.g. learn a new language), but which are hard - gamification helps, but won't be enough to keep me learning. That's just my personal observation. I do not know if it applies to others.