So here we have to new IPs from Nintendo, something that fans were asking for quite some time. Splatoon is a TPS based on territorial control set in a cartoony world, while STEAM is a turn based strategy game set on a comic-like steampunk alternative history setting. Both were announced at the same time, on E3 2014.However, Splatoon triumphed saleswise, reaching one millon units sold in less than a month on the system with the smallest userbase of the gen, being the best selling completely new IP on the WiiU and turning into a system seller in every region. STEAM, however, has not reached the 10k yet on the system with the biggest userbase of the gen (I don't even know if it has pased 5K), and being one of the worst selling first-party title on the 3DS.

What happened? How come Splatoon steamrolled (hehe, combined pun) STEAM in such a curbstomp competition? Granted, Splatoon had better advertisement and less cometition against the WiiU library, but it's still an abysmal difference.

EDIT: VGChartz has the game at 0.03m, or around 30K. Not as bad as I made it sound, but still the worst selling first party title on the system.

Splatoon is a ton of fun and STEAM was just meh?

One genre is much more popular right now than the other.

steam would work on steam alot better, its not a handheld genre. but the game realy looks fun an the trailer is the best thing since nintendont.

Codename steam's gameplay and style was unappealing

You also ask? Lol
Marketing...

^^^^^^^^^Yep, basically what everyone said.

Splatoon is a lot more interestong and unique looking as an online shooter.

That, and they pushed the hell out of Splatoon, and not so much with S.T.E.A.M.

Because honestly, Code STEAM looks like garbage (or "is unappealing")...
I'm a huge fan of Intelligent System and TRPG and I was thrilled when I saw a news talking about a new Intelligent System game. But after the first video, I lost my interest in the game for ever : I don't care about it anymore, not at all, and I will never play it. I just can't play a game looking like that :/

I thought the same. I loved the gameplay on the demo, but the story and the characters are not appealing at all. If this was reskined with a similar artstyle, story and characters as Valkyiria Chronicles or other anime games, it would have at least cattered to an scpecific demographic. As it is, it's too cartoony and unnapealing (characters, story and artstyle) for grown ups  and it has a gameplay too complicated for children.