Whoever stood out.
as a scoundrel on say voidstar for example I stealth around a lot protecting doors and sneaking up to plant bombs, this gets me low numbers, low medals and low contribution so nobody votes for me.
Meanwhile joe sage who follows around players ignore objectives and spam heals gets voted by guys who just didn't pay attention to what happened in the warzone.
Joe deserves credit for getting high numbers, but MVP should go to players who make exceptional passes/saves in huttball, or cap or defend well in alderaan