User blog comment:Rappy 4187/Technical Update: March 10, 2015/@comment-1251315-20150312231408/@comment-452-20150316180342

Personally, I prefer knowing when I'm in a special statistical group. I assume there was a similar method used to select who received the "Wikia's top admins" emails a while back.

I think it's a useful tag for users, and admins, to be able to quickly see who the top recently active contributors are. It could even serve as a convenient short-list for admins who want to promote other users.

Sorting by edit count alone is not always useful as the top contributors by edit count may have been inactive for years.