Codename S.T.E.A.M. is a great game, a very good production. I´m loving it.

But it´s an strategy game, and a quite difficult one. That´s not the kind of game that appeal to the general audience, it´s more like a niche game.

Reviewers on websites and magazines also didn´t do a great job in reviewing it. Most reviewers seem to have played only a few minutes and wrote their reviews based on a very limited portion of the game, then several low scores.

Splatoon, on the other side, besides getting a lot of advertsiment, is more appealing to the average gamer for its light, colorful atmosphere, quirky characters and focus on gameplay

Marketing, artstyle, genre, quality

Artstyle
Genre
Promotion/lack of such with Steam
Platform

Steam was never going to be Splatoon but I think it would have done better on the Wii U or earlier in the 3DS's life.

Cause STEAM is better

Not that I think Steam's sales are good, but I doubt VGC has anything close to reliable numbers on this game.

Judging on how quickly Nintendo ended the promotion for this title and the fact noone seems to talk about it (or even remember it after all this time), I'm sure the sales are still bad and way below Nintendo's expectations. The EU and Japan numbers haven't arrived yet, though.

i think less push for it...

I liked the codename steam demo but the overall reaction from the media and people online was patchy and though i thought i might like it this time i didnt feel like taking the risk (not ruled it out as a future purchase). There was a lot of buzz about splatoon and it was low price in the eu so i grabbed it day one.

STEAM was just a mediocre game with western heroes that Japan and most of the world has zero knowledge about nor interest in playing as. Lincoln vs Aliens... Like really? Inteligent Systems tried to balance the cast by throwing those Fire Emblem amiibos in there but it didnt work, even western gamers werent excited about this game so that's that.

Splatoon however, is a online shooter with no voice chat where you have teens in school uniforms that shoot each other with ink and can turn into squids... Million seller right there.

a online turn based fps, where you sit around waiting for your opponents to end their turns.

vs

a online fps based tactical game, where you get to be a kid and spray paint everywhere.


Geez I wonder why...

In short : dont make turn based multi player games, it doesnt work.