Why didn't Fiora get a new skin?

Both Gangplank and Mf get new skins with their VU's even though they have a lot of skins and more recent ones too... I've been literally waiting for years now and had RP sitting on my account for so long because I told myself I wont purchase anymore RP until Riot gives me a product I desire. It's so frustrating to see Ahri getting a skin every 3 months. Not to mention I can't even play the updated Fiora....