For most of the Convention awards, the responsible committee reviews all of the self-nomination forms and uses those - along with personal experience with the chapters over the biennium - to decide the winners/runners-up.
For instance, the membership committee (Fraternity Vice President Membership and the Membership District Directors) sets the award criteria for awards specific to membership, reviews the award nominations, and in committee decides the winners. In addition to the nomination form that the chapter fills out, their MDD will have had much contact over the course of the biennium, and she will know a lot about the chapter's membership program and how they have operated. (In other words, she'll know if the nomination form is accurate or "padded".) Same goes for the awards in all areas including Alumnae awards. College Committee (Fraternity Vice President College and the College District Presidents) determine the overall college chapter awards.
My memory is failing me at the moment so I can't remember the name, but there is one major award for a college chapter (and a similar one for an alumnae chapter) who has clearly excelled in all areas over the biennium. This is for one chapter, whereas the Golden Kite has no limit - however many chapters meet the criteria will be awarded it.
So, the awards reflect achievement over the biennium. Sure, some of it is based on self-motivation (you have to fill out the form and toot your own horn to be eligible). However, a lot of thought and information goes into evaluating chapters and selecting winners. It of course doesn't mean that non-award winners aren't valuable to the Fraternity. (How's that for a confusing string of negatives?!)
I hope this helps clarify a little bit. (This is based on my experience on Grand Council and is only as accurate as my memory.
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