My biggest problem with the Infraction system was that it was so impersonal. It was "2 demerits and a trip to the principal's office!" It was extremely insulting to me. It just felt like "You are a subversive individual." It says "We have no interest in working with you, we're just going to give you some black marks (which will never go away) because you broke these rules". That may sound ridiculous, but Infractions were such a blunt instrument that I never used them and encouraged every site admin NOT to use them.
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A demerits system (which is what Infractions really are) is an elementary school grade solution. I think most of us are past high school so let's look at something a bit more educated and flexible shall we?