I still don't understand why Zoe suddenly started taking Electrocute.
Her mechanics haven't really changed. Comet, Aery, and Electrocute haven't gotten changed. It's no easier or more valuable to proc Electrocute than it ever has since Zoe's introduction. Why does she take it now?
It just feels like Electrocute is so difficult to proc when her kit revolves around a single, long-range skillshot. You need to get in close enough to autoattack to get enough hits to proc Electrocute, which means sacrificing Zoe's greatest strength (range) for extra damage. At that point, why not just play some other burst mage like LeBlanc or Ahri that has better mobility than Zoe?
Is it her "best" rune because people just aren't playing Zoe into unfavorable matchups, so the ones where she can abuse Electrocute are the only places she's taken? Or is there something I'm not getting?