Darius, I think that "motivations criris afterward" must also be considered in the planning and prior call for Wikimanía volunteers and can be avoided. In Mexico we always tell to people that we did not want them just for giving the best of themselves for three days around, but we wanted to keep them with Wikimedia mission. A month ago we broke a Guinness record and 60% of attendees were Wikimania volunteers. It is a matter of long preplanning, I think.