The ones I've listed as dropped (I have plenty more) are these:
Hello my teacher. Gong Yoo was not believable as a student, and the show was just silly. Not funny silly, just why am I watching this-silly.
Boys on the run. I only tried to watch this because I was curious about Ueda's acting, and his role was interesting. However, rest of the show was not, and since he didn't get much screen-time, I gave up.
Faith. I'm not that big on time travelling in the first place, and this had an annoying female-lead and nothing interesting going on. I just wasn't able to focus on the show at all.
Honey and Clover. I've tried it. I've tried the manga, the anime, and now the drama, and I just can't. I simply dislike the idea of it. It has great actors and I wanted to be able to watch it to the end, but fact still is: love triangles. I hate them, and this show is way too full of them.
Love Rain. I'm just not into the whole flashbacks to some old love-thing, I got enough of that watching some other series. So even though this could've been really good, I got annoyed.
Nihonjin no Shiranai Nihongo. I don't even remember what this is.......
Que Sera, Sera. Started out great, I loved the main-female which is very rare of me, it just looked like it was going to be great. Then things happened, it went bad, I had to quit. I just checked spoilers on what was going to happen in the last episode to give me closure.
Stand Up. Again, great actors, but I just can't focus. Not enough going on to interest me.
Sweet 18. Hahahahahhaha oh gods. So dull, so bad, so nope. I can't believe it took me so long before I dropped it.
So basically my reasoning to all is either: I don't like the plot, or majority of things are too boring to keep me focused on it.