Its the women, all of the lady interests ruin the show, rita was interesting for the first season but then the british snatch shows up, horny is not a character type, they tried for crazy but they tried to hard and went so far it was just schizonympho and her being the one to kill Doakes was unsatisfying to say the least.

Miguels wife only existed to delay and ruin plot lines, her characters substance was nothing but a rabblerouser and a brick in the road, while not a love interest she still was a catalyst for too much interference between dexter and miguel.

Lumen had the chance to be interesting until she left and were back to mopey dexter so the same cycle occurs when it could have broken and moved forward. This likely goes back to the bitch who played deb having off camera issues with the other actors, many wont deal with a hostile work environment. The season also suffered from a very uninteresting main villain, a mad dog needing to be put down makes a good one off character but they do not make for satisfying story arc villains.

Hannah McKay was tue worst decision of the show, not because her character is unlikeable, she was written to be unsympathetic towards and that's fine, but that actresses line delivery was abysmal, the lines written were as if the writer had never written a female part, the sex scene on dexters table was just dumb it went for shocking and out if character but it just felt forced, the sexual tension in that whole episode was worse than a bunch of boys at summer camp at the cusp of puberty.

Finally, the doctor, way too god damn late to be psychoanalyzing dexter way too god damn late. By this point you, the viewer, are deeply familiar with dexter and his mental states, you dont need them drawn out technically and their own spin on it ruins the thoughts of the viewer, the ones weve been forced to develop over 8 seasons because its only at season 8 do we have an outro/introspection of dexters character, we no longer had need of it due to seeing seven other seasons, what we were force fed was insulting by that point. In fact the whole season was a big middle finger to those of us who actually stuck with their garbage we waited through all the shit and trash and get rewarded with the surprisingly dedicated father abandoning his child to a psycho to go and punish himself by being a mountain man.