I'm responsible for one of the 7's in the poll. I thought I might spell out why.
Primarily, it's because the ending is just too trite. This show had a lot of potential in the middle-to-later episodes to take the story in different, and potentially more interesting, directions, but at the end we're left with Shouko X Hiro and Karada X Tetsu. I've already expressed my feelings about the inappropriateness of the first pairing
here. Let me just add that Hiro's renovation in this episode is a mystery to me. I still don't think he's worthy of Shouko.
I don't have a problem with the latter pairing; it seemed inevitable from the start.
Perhaps my reaction comes in part from having waited so long to see episode 12 and feeling rather let down, not because the series came to an end, but because of the way that it ended. It's not that I didn't want closure, but I wanted closure to result from the characters growing in a way that made the ending plausible. Just what, exactly, made Hiro suddenly so appealing to Shouko? I know she loved him before, but that was a long time ago in a far-away land, and we were given very little information about the basis for that relationship. Perhaps it was just the result of two lonely people who shared a common background encountering each other far away from home. That might be enough for an affair, but is that enough for a rich life together as adults? I'd say no.
Regardless of how nice Hiro is to kids who come to pharmacy, what exactly is it about him that attracts an obviously intelligent woman like Shouko with deep, unexpressed wells of emotion just waiting to be tapped? I don't see Hiro as her companion on a journey of mutual emotional release and self-discovery; he seems pretty detached from that part of his personality. If Shouko has decided to latch onto Hiro simply to cope with the loneliness she expressed near the end of this episode, that's not a very good basis for a long-term relationship. I suppose she could be blind to her own motivations with regard to Hiro, but she seems too intelligent and too self-aware for that to be true.
I'm willing to be convinced that I've been too hard on Hiro if anyone wants to try.
Regardless of my feelings about the story, let me hasten to laud once again Shouko's seiyuu Itou Shizuka for yet another fine performance. I'm only sad that we didn't get to hear her more often in the latter half of the series.