You know, the awesomeness of character interaction dialogues vs. the stupidity of the overall plot convinced me that there are 2 groups of writers for ME3. One group handles the minor dialogues and character interactions. These groups know what they're doing. They're the ones who produced Liara's time capsule sequence, the character interaction moments, and just basically the consistency of characters interaction.
The other group, which I assume to be the head writers, handle the main plot. And for some reason, they just don't bother to incorporate the good stuff that the other group has done. For example, Liara's time capsule would have made for a touching ending if it's discovered by someone. But was it even there? NOOOO. To top it off, this main plot group doesn't seem to know what makes the game great as a whole and just assumed that out-of-nowhere ending is the best way to end this series.