What went wrong with TLH?

Personally, as an extremely avid reader now, I credit Cassandra Clare with my love for it. I love getting immersed in worlds with rich characters, found families and adventures and I find myself, all these years later, seeking out stories to similar to the ones I fell in love with as a young teenager.

Even today, I'm mid 20s, but her series are still some of my favorites. They're comfort reads I go back to time and again. TMI, TDA and TID. I love, love, love them with all my heart.

But TLH....... I read them all, and found each book less engaging than the one before it. Why?! What changed about this world I love so much? I wasn't invested in ANY of the characters (but I found Jesse and Lucie most compelling) Did I outgrow it? I really don't think so. I was just bored and detached for the whole trilogy, it was a chore to get through.

Did anyone else have this experience? Can anyone pinpoint what feels different about that series compared to the others? I don't know why it was such a flop for me!!!!

Anyway, I'd love more books on any of the other characters, or new characters in the Shadowhunter world....