Platinum Games' Bayonetta 2, a Wii U exclusive published by Nintendo (NASDAQOTH:NTDOY), is off to a weak start in Japan.

According to industry tracker Media Create, the third-person shooter sold about 39,000 copies during its first week, finishing third behind Super Smash Bros. for 3DS and Yokai Watch 2. In 2009, the original Bayonetta sold about 138,000 copies during its first week in Japan, which was split between 93,000 copies for the PS4 and 45,000 for the Xbox 360.

Bayonetta 2. Source: Platinum Games.

The lukewarm reception for Bayonetta 2's lukewarm reception is disappointing, considering how critically acclaimed the game was -- Famitsu gave it a 38/40 rating, while Edge rated it as a perfect 10. Hardware sales weren't an excuse, either: Nintendo's Wii U is currently the top home console in Japan, with sales of 1.9 million, compared to about 710,000 PS4s. Bayonetta 2 will launch in the U.S. and Europe on Oct. 24.

Although slow sales of one exclusive title certainly won't sink Nintendo, it could discourage other developers from launching exclusive games for the Wii U in the future.

The business of Bayonetta
There are three main explanations for Bayonetta 2's misfire.

First, Super Smash Bros., which sold over 1 million units within its first two days in Japan, likely stole the spotlight from Bayonetta 2. Second, the Wii U -- which has a reputation for more family friendly first-party titles like Mario Kart 8 -- simply isn't the ideal platform for M-rated series such as Bayonetta. Third, Japanese gamers heavily favor handheld titles -- of the country's top 10 games, four were 3DS titles and one was a PS Vita title.

Expectations shouldn't have been particularly high to begin with. The original Bayonetta got off to a better start than its sequel, but it ultimately sold just over 2 million copies on the PS3 and Xbox 360. To put that into context, the top 10 best-selling games on the PS3 sold between 7 million (Battlefield 3) and 18 million (Grand Theft Auto V) copies worldwide. The best-selling PS3 game from a Japanese publisher, Konami's (NASDAQOTH:KNMCY) Metal Gear Solid 4, sold nearly 6 million copies.

The original Bayonetta. Source: Platinum Games.

Another possible reason for Bayonetta 2's weak start is that the first game wasn't available on Nintendo hardware. Platinum Games addressed that by including a ported version of the first game with Bayonetta 2, but that lack of familiarity among Nintendo gamers probably also hurt sales.

Why Nintendo needs more third-party exclusives
Bayonetta 2 isn't a third-party title, since Nintendo published the game, but it is a refreshing new outside IP that stands apart from the company's other first-party games starring its flagship characters. Bayonetta 2 was also considered a test of how more mature third-party games would fare on the Wii U, a platform dominated by casual first-party titles.

Of the top 10 selling games on the Wii U, only one -- Ubisoft's (NASDAQOTH:UBSFF) ZombiU at number 10 -- wasn't published by Nintendo. Most of the other nine games are platformers such as New Super Mario Bros. U, flagship character mash-ups like Mario Kart 8, or party games like Wii Party U. Therein lies the key problem for Nintendo -- it keeps selling the same type of games that were popular since the N64 era, with diminishing returns.

Mario Kart 8. Source: Nintendo.

Yet sales figures suggest Nintendo gamers simply aren't interested in the M-rated triple A titles. Activision Blizzard's (NASDAQ:ATVI) Call of Duty: Ghosts only sold about 180,000 copies on the Wii U, compared to nearly 9 million copies on the Xbox 360 and 8.3 million copies on the PS3. Ubisoft's Assassin's Creed IV: Black Flag only sold 200,000 copies on the Wii U, but sold 3.2 million copies on the PS3 and 2.8 million copies on the Xbox 360.

Therefore, it's not surprising that Ubisoft in August halted plans to sell new M-rated games on the Wii U. If Bayonetta 2 flops in Western markets as well, it could serve as another warning that third-party publishers shouldn't bother with Wii U games.

To understand how much of a pariah Nintendo has become in the industry, consider this -- there are now 37 games that haven't been released on the Wii U, but have already been ported to all five other major platforms -- the PC, PS3, PS4, Xbox 360, and Xbox One.

The road ahead is crumbling
In conclusion, Nintendo is basically stuck making the same games for a shrinking group of fans who still haven't turned to mobile games or core games for other platforms.

Looking ahead, Nintendo will need to jump between major first-party releases, like Super Smash Bros. for Wii U, the new Legend of Zelda, and the new Star Fox game to keep gamers interested without a safety net of third-party support. "Darker" first-party Wii U games like Devil's Third and Fatal Frame: Shrine Maiden of the Wet Crow might get some press, but they probably won't move the needle any more than Bayonetta 2.  

[Editor's note: Corrected statement of the 10 best-selling games on the PS4 to correctly refer to the PS3]

Leo Sun has no position in any stocks mentioned. The Motley Fool recommends Activision Blizzard. The Motley Fool owns shares of Activision Blizzard. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.