This skin isn't even an ultimate or legendary and it doesn't even look good altogether as an epic skin. How come the Battlcast Illaoi skin was getting constant preparation update to us than any other skin? I know people asked for a new skin for Illaoi but they also asked for new skins for other champions too. While they hyped us this skin like it was the next ultimate skin.
Lintu Puck2 votesBecause Illaoi had not gotten a skin since release, the fans were getting pissy and demanding a skin, so Riot chose to let fans pick 1 of 3 ideas and then they showed us on a regular basis what it takes for them to make a skin. The idea being Illaoi fans finally get a skin, while Riot tries to make it clear, with evidence, what it takes to make a skin.
SEKAI2 votesBecause Illaoi has not received any skin beyond her release skin.
And because this skin is chosen by the community. Riot released 3 skin concepts between 'Astronaut' Illaoi (space horror themed with alien tentacles), 'Adventurer' Illaoi (Indiana Jones themed, kinda, with vines as tentacles), and 'Battlecast' Illaoi (self explanatory, though Illaoi herself is not a machine but a resistance member who opposes the machinisation, a little bit like John Connor), for players to vote for. Whichever side you are on, 'Battlecast' Illaoi won and so it was decided that it is her new skin, now named "Resistance Illaoi" I believe. Hence Riot is constantly updating the progress of the skin's development.
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As for why 'Battlecast' won against 'Astronaut' and 'Adventurer'? Don't ask me. And don't question the integrity of the voting process either, because it was possible to multi-vote (given each account has 1 vote but each person can have multiple accounts) and obviously there were some people who abused that, but hey, let's hope each side had the same amount of cheaters.
UniSect1 votesLike I said, many champions havn't got skins since release also. While many champions havn't gotten skins since League ever started? Like Yorick. He lately got one but it took a lot of years. Maybe the answer is showing us the process of a skin but they haven't really showed us the process of making a skin but how long they make one. For the pictures they sent us were their process in the makings, not what it takes to make them.
SEKAI1 votesLike I said, many champions havn't got skins since release also. While many champions havn't gotten skins since League ever started? Like Yorick. He lately got one but it took a lot of years. Maybe the answer is showing us the process of a skin but they haven't really showed us the process of making a skin but how long they make one. For the pictures they sent us were their process in the makings, not what it takes to make them.
Most of the reason to why they update us on the Illaoi skin is at the "choose your own skin" bit that they hosted a bit earlier for Illaoi, which I also went into details on in my post.
Sona Ping1 votesThis skin isn't even an ultimate or legendary and it doesn't even look good altogether as an epic skin. How come the Battlcast Illaoi skin was getting constant preparation update to us than any other skin? I know people asked for a new skin for Illaoi but they also asked for new skins for other champions too. While they hyped us this skin like it was the next ultimate skin.
Simply because they wanted to do a behind-the-scenes and that was a skin that was both available and able to be showcased like that.
No, they did not "hype" it like it was an ultimate skin.
Disneylord1 votesThe skin was ruined completely, first they changed her clothes then they changed the splash art design and then they even changed the name, it lost all of its meaning now
Chembaron Yamada1 votesThey said right from the beginning of the vote that the pictures as well as the name are just placeholders, not what it will be in the end.
You were basically voting for "which base idea would you like for Illaois next skin?", not directly the skin itself.
Everything they presented was work in progress and they pointed out that there will heavy changes made until it reaches the state of being the final product. You just had wrong expectations here.
swordofsun1 votesThey said multiple times that they were doing this to show the behind the scenes process of creating a skin. From concept art to release.
Again, this was stated multiple times. They never promised anything super special with this skin beyond it being an Illaoi skin. They've also stated that they might continue to do this with other champion skin releases.
ModCaliCoastReplay1 votesMy girl 
is breaking out this season, and has only her initial release skin. There's a lot of interest and demand for the champion right now. I am exactly the demographic they're targeting - I play her and want a skin but don't love Void Walker. I am indeed planning a purchase of Resistance Illaoi. So, on some level Riot is doing its job. :)