Riot releases skins to champs that a lot of people play like yas and lux. Idk if riot does it for money or what ever fan service but you they should really open to other champs that have like 2, 3 or 4 skins, i know so many people that hate this.
Riot does that because those are the characters that are more popular, and thus skins that are made for them sell a whole lot better than one for a less played champ. That's also the case with Kai'sa. As a free to play game, Riot gives more skins to popular champions because its what pays the bills.
