And here I thought it was a feature, not a bug.
That's really the main reason why I loved this series. Instead of the main guy flip flopping between one girl or another for pretty much the entire series, repeatedly destroying whatever build-up they had for any girl by doing so, this show has Kouichi slowly but definitely surely growing towards Mao right till the very end. A great change of pace from your regular harem anime, or even from recent straight love triangles in order to 'avoid' becoming predictable. And for me, this series basically illustrates that being 'predictable' isn't a bad thing if it's well executed, just like with all other things.
As I quoted before in this thread, "There are no coincidences; only
hitsuzen." Every seemingly tiny and insignificant event points, and leads to, a single inevitable route. Of course, there's red herrings to keep things unrepetitive (ala Kai and Yuumi, and even then they took part in pointing to this inevitable route), but that's pretty much what I have been taught to look/write for in a good plot.