It seems like there were expectations for a full second season of Buddy Complex, e.g. from here in March 2014:
But then, only three months later, a two-episode finale was announced instead, seemingly to the surprise (a reaction of confusion common in other forums as well, which I share) of many. The finale was released in September 2014. The finale announcement article also concludes with the same note that "the story will still continue" but this seems to be more copy-pasted from the first announcement than an actual announcement (it links back to the same old Twitter post).
Why did Buddy Complex not get a full second season? Was a second season scheduled and then reduced to two episodes because of poor sales or anything like that? Is another season still planned? I don't know Japanese and so searching for sources was difficult. I'm looking primarily for official news and announcements, interviews, etc.