An interesting discussion of the need for systems to elicit self-control rather than brute force measures to keep would be evil doers away...
We’ve all gone to school on the moderation and reputation systems of Slashdot and eBay. In those cases, their growing popularity in the period after their respective launches led to a tragedy of the commons, where open access plus incentives led to nearly constant attack by people wanting to game the system, whether to gain attention for themselves or their point of view in the case of Slashdot, or to defraud other users, as with eBay.
The traditional response to these problems would have been to hire editors or other functionaries to police the system for abuse, in order to stem the damage and to assure ordinary users you were working on their behalf. That strategy, however, would fail at the scale and degree of openness at which those services function. The Slashdot FAQ tells the story of trying to police the comments with moderators chosen from among the userbase, first 25 of them and later 400. Like the Charge of the Light Brigade, however, even hundreds of committed individuals were just cannon fodder, given the size of the problem. The very presence of effective moderators made the problem worse over time. In a process analogous to more roads creating more traffic, the improved moderation saved the site from drowning in noise, so more users joined, but this increase actually made policing the site harder, eventually breaking the very system that made the growth possible in the first place.
from alex3f 
