There Is No Antimemetics Division was GREAT, but...

I am trying to keep this spoiler-free:

I loved this book. Flew through it. Really liked the world-building and the characters. The conflict was intriguing and left me wanting more.

Why did the ending have to be so bad? It was as if in the last 30 or so pages qntm just... gave up. The climax was incredible, but then the falling action and conclusion took away everything that made the book so interesting.

I'm curious if anyone else feels this way, or if it's just me.