I understand that mod terms are for life. However, I find it odd that Mi.Yodeya has had the second least recent elections of any site on StackExchange. We have not held moderator elections since 2012. The majority of StackExchange sites have held moderator elections as recently as 2015, with only 5 out of 55 sites having their last election longer ago than 2013.
(Mi.Yodeya is one of these five; the other four are Physics, Android Enthusiasts, Tex-Latex and Drupal Answers. Of these, only Tex-Latex had their last election longer ago than we did.)
I haven't been able to find any official Stackexchange policy stipulating a frequency for elections. But if other sites can manage to have them regularly, why don't we?