Analisys of rep on different sites
I think that some of the objection to rep comes from different site cultures where rep wasn’t that important, or not much of a motivator for the top users. I’ve thought about this a great deal, and it seems that certain site characteristics make rep unimportant, while others make it vital.
My main site on SE was Electrical Engineering. There, rep was a strong motivator for most of the top contributors. The site simply wouldn’t have been anywhere near as successful without rep. However, on other sites that I participated in, rep didn’t seem to be all that relevant. So, what are the differences, and why?
It seems that sites where the top content contributors are professionals in the field are those where rep matters. These people are there because they are interested in the topic and probably at least somewhat enjoy teaching it. But, that by itself isn’t enough for more than the occasional answer here and there. Rep provides the public recognition as a reward for lots of good contributions. That kind of recognition is valuable to these professional contributors, and draws out a lot more participation than otherwise. I know this from personal experience, and I’ve talked to enough other EEs to know that I’m not the only one.
As evidence, take a look at the users on EE.SE with 100k rep or more. I just checked, and there are 8 of them, and every last one is a professional in the field. Also note that the top 6 users all give their real names, mostly right in their user names. The top 6 also have their real mug shots as avatars. Unlike most users on most sites, they are not trying to hide. In fact, they want you to know who they are.
The one possible exception to the rep is important to the professionals rule may be where those professions already provide other means to be known among their peers and potential “customers”. This is the case for academics, for example, with their scientific paper publishing network. A good example of this kind of site is Physics. The top contributors are academics in the field, but I don’t know whether rep is much of a motivating factor for them. I noticed a few refugees from Physics are here (@dmckee), so maybe they can chime in.
An example of a different type of site is Photography. There, the top users are amateurs with day jobs in different fields. I always thought it was disappointing that there weren’t more active professionals. It didn’t seem to me that rep was much of a motivator. I know it wasn’t for me. I was there just for fun. However, also note the significantly lower participation rate. The top user has only 150k rep, and there are only 3 over 100k. The top users are also less active in terms of answers/day, don’t show their real faces as much, and don’t use their real names as much. This all fits with being there for fun rather than viewing it as a professional activity. Despite that, we have one user (@mattdm) who stated that badges motivated him. This again fits with the non-professional. Badges are shiny things to collect for fun.
Conclusion
Rep doesn’t matter much on some sites, but is critically important to other types of sites. The software must recognize this and be built with the capability of computing and displaying rep. Sites that are really against rep can have the ability to turn off the display (there is no harm in the software still computing rep, so just turning off the display is less complex).
I suggest that rep here should be the sum of votes received on all answers by a user.