User blog comment:Mineko Charat Lucky/Ward skins, why doesn't Riot expand on them?/@comment-5774371-20130415131553/@comment-4022742-20130415163446

Making a set of standard wards you have to unlock to use and have infinite uses of. And another set of wards that are 1. limited in availability or 2. seasonal. Is actually exactly what they do for champions and free week with skins that are only available for a season.

So what exactly is the problem with more ward skins that are purchasable by IP/RP?