I didn't read the webtoon so I do not exactly have much to say on which one was a better landing. But I do know I enjoyed the drama well enough.

Just a word of thought though. Adaptations can be very tricky. There's the risk of following the material thoroughly to the point that it lacks ingenuity and flexibility even though its original. And there is the risk of it insulting its roots when the source material is taken for granted and used flimsily or without regards to the adapted or like the mess Business Proposal did. You know, for BP, it took reading a fixed ending to know what sort of a huge mess BP was with its ending and it was a major comment to the school of thought that adaptations should be strictly adhered to. But that's aside. All in all, I just hope adapted dramas stopped being critically screen when they veer off the expectations of viewers who have read or watched the adapted material. DB was well reasonable on how they critically criticized SYIM19L for going off material sometimes, but some forums weren't as forgiving.

SYIM19L was better than the webtoon? My biased answer will be yes.

Is there anyone who read the webtoon and watched the drama?

Of course the drama adaptation is better than the source material! Adaptations are always better! ALWAYS! There are no plot-holes, the drama was perfect with its logic from beginning to end!

@vienibenmio this is your thread! Please enlighten us!

Webtoon is overall better, no doubt.

But the real problem with the drama is not that it's different but that it is not that good itself.
The pacing, the editing, sometimes the script are not great.
For me it started fine, but slowly went downhill (like its ratings 😭) and never recovered, and by the time I watched the last episodes I just didn't care anymore..that's never a good sign.
I mean, I've been anticipating this drama since last July!! I really wanted to like it, it just didn't work out 🥲

I don't know how ANYONE who read the comic could agree that the drama was better! I should have known after Kiss Sixth Sense barely resembled its source material, but I had high hopes because of the cast, the creative team, and Lee Hye being involved with the production. I should have known, though, that drama adaptations of webcomics apparently are incredibly unfaithful to the source material. Even fans of Summer Strike and A Business Proposal (btw, I loved that drama so no complaints from me there) said as much. Is Yumi's Cells the only exception? Not sure.

Anyway, the comic was actually quite a fresh and modern take on the reincarnated love trope. The drama took all of that and turned it into the same tired cliches we've seen over and over again. There was no need to change any of it. And the drama just BUTCHERED it. I don't know why they even bothered adapting it if they were gonna change it that much. The webcomic's theme was about choice, and the drama made it into a theme about predestination. Pretty much the opposite. If you're gonna adapt material, it's fine to make changes, but when you change themes I'm gonna throw fists. Not only did they change major plot points, they even changed the ending! THE ENDING. They added in a bunch of unnecessary angst that complicated the series and made a story that I was already worried about fitting into 12 episodes even more bloated. They also changed the atmosphere. The webcomic was quite lighthearted and even funny--perhaps too much, considering the story content--but the drama was SO SERIOUS all of the time. I missed some of the funniest moments and jokes from the webcomic.

The comic also placed the characters and relationships first. Ji-eum and her relationships with Seo-ha, Do-yun (yes, in the comic she has a relationship with Do-yun, although it's never romantic), and Cho-won were given top priority. The drama barely focused on the relationships. Poor Do-yun and Cho-won's story was slaughtered. The scenes that they left were rushed. They left out a lot of important story development in terms of both their relationship and Do-yun as an individual overcoming his reluctance to being with Cho-won. They decided to set their romantic scene, which was incredibly intense and romantic in the webcomic, next to a pool for some reason (what is with this director and pools, btw?) when it was supposed to be outside in the rain, mirroring how they met.

They also added in a bunch of weird complications and cliches that the webcomic avoided. They made Seo-ha, Do-yun, and Cho-won all in Ji-eum's first life. They made Min-gi all mysterious and knowledgeable. They made Seo-ha's father a jerk (yet they kept the ultimate ending they gave him, which was perplexing given how different his character in the drama was). They added an evil stepmom-type figure for some reason. They added weird things that they spent way too much time on, like Seo-ha sitting in pools, and a lot of scenes about...

I have already been burned many times of adaptation vs source (GOT, Witcher, etc) so for my peace of mind - I don't compare and just consider adaptations as an independent material on it's own. Viewed as such, I did like the show.

Deep breath. This is a painful topic right now.
I want to start with a comparison to Howl's Moving Castle. I love the book to pieces and I think Miyazaki's adaptation is stunning. But actually there are only a few key similarities between the two. Yet, it works because the movie takes the essence of the book to make commentary on the relevant issue of the cost of war (in the book the war is barely a footnote) while keeping the best of the Sophie and Howl.
If the changes had served a understandable purpose and if the end product could have stood on its own, I would have been fine with the changes (I think). But, the way See You in My 19th Life was adapted made no sense and felt more like a betrayal of the characters and themes of the original. SHS was wonderful as Ban Ji Eum, who is quite an unusual character in that she has qualities-- like her straightforwardness and extreme confidence--that are more often associated with a male lead. And the remaining cast did well with their characters as well. Truly, the acting from the kids to the main 4 was delightful.
It was the writing and directing choices that disappointed me. The emphasis on angst and overuse of the crash to the point it lost all emotional power. The additional character of HaNa (what?!) and the added consequences of knowing about past lives for Jieum's loved ones (are you kidding me?) served no apparent purpose except for angst for the purpose of angst. I honestly do not know what the writer and production wanted to say here. It was just dreary--beautiful to look at but painful to watch.
The webtoon on the other hand keeps the balance of humor and drama with time spent on relationships between the main four characters. It is witty and thought provoking at the same time. And you just feel GOOD reading it.
I regret what it could have been.
I now know how Cheese in the Trap fans felt. Ugh.

Honestly when it comes to webtoon adaptations there's bound to be issues. From what I learnt during my time watching dramas its either they stuck to the webtoon too much (direct print to screen) or didn't stick to it enough(changed/reduced scenes, added stuff etc).
Either way there would still be people raising issues about it so it would boil down to ones personal preference I guess?

For long-term fans of webtoons it might hurt more as the plot we all know and love has been changed and "butchered" into something that takes the meaning out of the story we initially fell in love with and I get it. If they adapted any of the webtoons I love, especially Positively Yours in the future I would rage hard.

I am a firm believer that an adapted work needs to stand on its own merit.

Unless you are the creator/writer, director and producer of the work, those adapting it will want to put their spin and opinion into "their" product.

It does bring up the question whether webtoons are good source material for dramas. Webtoons are story boards of situational events while literary works are long prose, mental picture painting. One could argue that books offer more character development and less leeway than a webtoon adaptation.

I'm tempted to watch the drama now that's concluded and I've seen some of the comments. I've read the entire webtoon but I don't remember it as clearly @vienibenmio and my takeway of the webtoon was definitely different than theirs so I'm curious about how I'll intrepret the drama.