Reputation.

[SparoHawk]

Well, I understand what you mean.

As I see it, you can thank anyone for anything. You'll eventually find yourself thanking one user in particular multiple times. However, you will not go hunting down for all of that user's posts just to thank him on every single one. Mainly because you won't feel the need to thank him for a post where he describes his graduation experience, or w/e.

Now, thanks will come and go as the threads come and go, but, reputation stays on the user profile as a permanent mark on how helpful or troublesome he is for the community. There is not a "No thanks" button, so the only way you can let know people of someone who is a troll or of similar kind is by going to his profile and giving him a negative rating with an added comment, something the "Thanks" button cannot do.

And there is also the fact that you can thank someone and not care for his reputation. It just, kind of, different commodities to be used individually.

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Now, I'd like to know why you can give more than one rating to any user.