Well, I refuse to watch most romantic comedies and some overrated "nonsense" here and there. No offence to fans but things like Heirs, Mary Stayed out all Night, Heartstrings and Pretty Boy or whatever are things I will never watch.
I also refuse to watch anything that my blacklisted actors take part in no matter how great the drama sound. Like skipping I Hear You Voice and 14 Days forever because Lee Bo Young is the female lead.
Tragic and too melo stories such as Koizora, 1 Litre of Tear, Sunny and the rest don't fall under my interests as well. I dislike those types of productions.