Instead of asking the usual, I was wondering if anyone has any suggestions for which kdramas I should NOT watch at all costs due to a terrible plot, horrible acting, etc. Thought this would be fun and useful. Thanks in advance!

The Heirs. I couldn't even make it through an episode.

I have heard Nail Shop Paris, Playful Kiss, and Fashion King were terrible too but don't care to find out for myself.

Then there are ones that I personally think were horrible, but many people like them so I won't add them as ones you shouldn't watch since our tastes might differ: Coffee Prince, Secret Garden, and Boys Over Flowers.
I loved Nail Shop Paris! Haha! You just can't take it seriously is all. :p

Anyway, here are the KDramas I would advise you to avoid:

1. Cheongdam-dong Alice. This drama caused me no end of frustration.

2. Secret. So many people loved this drama but I thought it was awful. 

3. Spy. I ♡ JaeJoong but this drama was such a waste of his talent. >_<

4. East Of Eden. Heavy, heavy makjang. Lots of man tears. >_<

5. Mary Stayed Out All Night. I wished she never returned. The drama would have at least been a smidgen better without her whining. >_<

6. My Unfortunate Boyfriend. I felt very unfortunate that I forced myself to endure it. >_<

7. Flower Boy Ramyeon Shop. Aigoo. I can't even. >_<

8. Yong Pal. Even Joo Won's face and Kim Tae Hee's hair could not save that trainwreck of a drama. >_<

Really? The Heirs is not bad tbh. In fact, its a must watch!
The Heirs is pretty close to the worst drama I've ever watched but I understand why people like it

The ones that I really recommend you don't watch are Missing You (the actual worst) and The Thorn Birds (total snore fest with the most unlikable characters ever).  An anti-recommendation with a caveat is Descendants of the Sun if you watch this stop after episode 14 the last 2 episodes are like being repeatedly punched in the face by the writers and production team.  I would have given it 7 but the last two eps made me lower the rating to 2.
I literally had my hand on my heart while reading the other answers haha.
Even though maaany people love them, I still believe that these dramas were a waste of time.
Bridal Mask and Scholar who walks at night. In both, I love the actors, some specific scenes e.t.c however, both of them made me feel like every minute is an hour and made me very frustrated... 
@Fabiya: if you want a personalised answer, you might want to list a few dramas you haven't enjoyed :)

Everyone opinion here is very different. I for example really enjoyed watching Mary Stayed Out All Night & Scholar Who Walks The Night (though they really could have scrapped that ridiculous romance in the Scholar lol) 

Then again I really didn't like the webdrama Imaginary Cat, which was recommended to me a couple of times and quite heavily praised. For a webdrama that is supposed to be short, it felt to me like it just wouldn't stop. The irrealistic behaviours & (over)reactions of the characters were also quite irritating to me. But then again, I guess it might be the problem webdramas face because they need a simple plot & minor plot-twists with limited time & budget. 
I've just started Noble, My Love (another webdrama, also heavily praised), and it's giving me exactly the same vibe. What is it with webdramas that star animals in it? ^^'
Imho, people should explain why they dislike....bcz people have various states.

Dropped or could barely finish ... bad writing .and/or.  bad acting  .and/or.  boring/senseless plot  ---> Nothing worth watching
---> Goong S ..... ..... couldn't make it past Ep 2 ... silly/stupid
---> Fashion King ... .... I really tried for Yoo Ah In ...But No! dropped .... very lame!
---> Pretty Boy  .... .... despite the cute 2nd lead...No!
---> Heartstrings .... .... Inane .... no need to say bad acting ..... some may like the music.
---> Marry Him if You Dare    .... .... Yoon Eun-Hye couldn't save the insipid writing.
---> My Fair Lady .... .... Some may like the cute scenes... just boring to me.
---> When A Man's in Love .... ....  Whey?... why would he love her and why would she do that? Most annoying female lead .... Poor SSH is very hot here!

Had problems ... But some things were worth watching
---> The Heirs .... .... the writer must have been drunk, bcz she couldn't remember what she put in previous episode ..... But side characters were fun.
---> Goddess Of Fire, Jeongi ..... ..... supposed to be an interesting story ....  fail to make me care ... ... and some bad acting!
---> Sword and Flower .... ..... something was missing ... lacked depth, cohesion, interest, etc
---> I Do, I Do ..... ....  Blahh! ... interesting noona romance ... Some good things but not worth the time.
---> Protect the Boss .... ..... Funny, interesting ... good start .... got very draggy at the end.


I disagree w/ a few that people mentioned ... as some may have the good outweighing the bad .... ... 
But especially ... 
East of Eden .... is one of the Best K-dramas .... Amazing Writing, amazing Characters, amazing Development, very good acting, and so Well Thought-Out !!!  .... .... Ohhhh what a Very Interesting premise and Story!!!  .... Intelligent/realistic devolopment.
Yes!  it is a Melodrama, but Not at all cliche!! ...
DO NOT watch if u don't want to care/cry or want depth ... DO WATCH for a well told, very interesting story!!


Absolutely 1000% TEMPTATION - where do I start with this horrible drama? Just recalling its atrocious events still infuriates me. Glorification of immorality of the worst kind, selfish despicable lead characters, misogynist in ways that are totally indefensible and intolerable ... just all round terribly written, terribly packaged ... everything about this drama stinks. Save yourself the trouble and stay far, far away.

WHEN A MAN LOVES - as someone mentioned above you're going to want to bitch slap the female lead, not to mention the girl who plays her can't act for sh--!
Has its moments, but not worth the frustration, imo.

LOVING YOU TEN THOUSAND TIMES - a very nasty mess of a makjang. One of THE most annoying female leads EVER. I have still not forgiven the actress.

MY SUNSHINE - a lot of people loved this and I wanted to love it too because of fantastic Wallace Chung, who was so bone-meltingly sexy in this role. Unfortunately, they paired him with a spineless woman-child that totally killed any potential for a good, adult romance this had ever had. A very mismatched couple in every sense of the word. Moreover, if intimate scenes bordering on rape is not your cup of tea, just don't bother touching this one.
It was already mentioned quite a few times, but I still have to name it: Fashion King To be honest, it was one of the first dramas I dropped and it had a rather big impact on me, since it was my first time watching Yoo Ah In and Lee Je Hoon. Nowadays I luckely know that they are great actors (s. Thrones or Signal).
Another one I dropped was Time Slip Dr. Jin I didn't like the story and the acting. I only really cared about Jin Yi Han's character, who wasn't even a big role.
My Lovely Girl, The Heirs, just didn't do it for me.
Angel Eyes <- only watch the first few episodes with the younger parts. They were so good, but afterwards I just dropped the drama.
7th Grade Civil Servant I thought this was drama really annoying.
The Heirs, She is Wow, Glowing she... I felt like that was time wasted when watching those.
Do not watch Secret Love Affair; i wasn't interested in it from the first place but I watched it because of some comments i read about it that there were some life lessons in it and it leaves deep feelings in you or such.... it was all nonesense..! It was one of the dramas i literally regreted the 16 houres i wasted to watch it.
Some other dramas that doesn't worth your time:
High school king of savvy
Orange Marmalade
Pretty boy
@emylan

could tell us the reasons behind your choices? High school king of savy & pretty boy are on my PTW list, so i'm curious! (i was always a bit hesitant about pretty boy actually and was considering taking it off my PTW list)

as for orange marmalade, i can understand that all the time twists are confusing and don't make sense, but i still found it an enjoyable show to watch, so i'd be interested what of it you thought wasn't worth your time :3

thanks! <3
Is it just me or I could't stand To the Beautiful You ?
u  guys arent romantic at all how can ppl say to the beautiful you the heirs boys over flowers coffee prince scholar who walks the night playful kiss those are classic romantic movies come on guy let me tell u what is crap my lovely kim sam soon and birdie buddy now thats crap aish it pained my eyes and ears watching and listing to those type of movies total crap