I would say they were "lackluster" and the unexpected graduations made their situation worse, but I would never consider them failures.
I means, Ogawa and Yuuka fans still blame 2nd gen up to this date, which is annoying af. If only they announced Ogawa's graduation months before, the audition and 2nd gen wouldn't received such negativity (at least in my opinion).
Anyways, Country Musume / Country Girls had a history of auditions in which they either only found 1 girl (Kimura, Satoda, Saitou) or none at all. I'm sure there are girls willing to audition for non-Momusu groups, but they just don't get that same hype level and a Morning Musume audition.
S/mileage didn't bothered having an audition because they wanted to change as soon as possible (which they did) and adding from Kenshuusei is so much easier. It's possible for ANGERME to have a 4th gen audition, but only the future would tell us.
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On topic... Suzuki Airi said that the last episode on Buono!'s radio show there will be an announcement. I guess it could either be Buono! disbandment or Buono! comeback, it all depends on Miyabi.
