"Drop" implies I've been watching it for a long period of time, but...
I did a first-watch marathon of The Walking Dead last summer. SPOILERS AHEAD Zombie storylines aren't really my thing, so I was forcing it through most of the first season to understand why it was so popular. It really picked up after season 2 until I was hooked. As soon as the show got to Alexandria, it slowly started to go downhill. Everything Negan was horrible and went on way too long. I thought the most recent season would be better because he seemed to be finally done with, but then Rick died. I stopped watching after that. There were several others I liked (Carl, Glenn, Maggie, Maggie's Dad, I even started to like Merle at some point), too, but Rick, Michonne, Daryl, Carol, and Carl were the characters that kept me watching for as long as I had. I was especially amazed at what they did (or the comics apparently did?) with the latter three because I didn't like any of them initially and they felt like the types of characters that in any other show would've been shed as fodder along the way: Daryl would've died in the first season as an antagonist, Carol would've been disposed of after they'd wrung out all the drama/tears over her daughter being dead, and Michonne would've died fighting The Governor at some point.
If I were to ever watch again, the episode where Michonne talks Rick into having hope again and they drive into Alexandria would be where I'd stop. That feels like a good ending, especially following not long after the episode with the storm where they call themselves (rather than the zombies) "the walking dead."