Just wondering what other people think of this, I think a lot of games i would have enjoyed a bit more if i never watched the anime. Not just because of spoilers but seems like most animes show everything expect the ending of each character so when you play the visual novel you know basically everything till you get to the end of the story.
Pretty sure there was a thread about this. Anyway, anime adaptations don't "ruin" visual novels, they're just an adaptation of them. But I too wish I would have played some VNs first before watching a series because I've found how great VNs are - originals of anything are always better. But I don't regret watching anime I have really enjoyed that do have a VN, like Clannad and Steins;Gate. There are other anime I have watched and enjoyed with a VN and I will get round to playing them at some point; some I've watched people usually complain that the VN is better. I'm now a lover of VNs, though still an amateur.
Find out if there is a VN before watching the anime and you won't have to go through with what you don't like, unless you already do that and didn't with past titles.
It depends on the direction the production company takes when adapting other works. There are examples of both good and bad adaptations.
But there's one bad example that stood out the most to me, Oretachi no Tsubasa wa Nai. Considering the way the original VN plays out, there's no way making into an anime can properly express the story.
Usually to blame is the Studio handling the titles.
While the original VN can be a "mind blowing" experience with good story/comedy/ whatever makes it popular. But there's no guarantee that any adaptation is good.
-IT's always a difficult task to adapt a 30-50 hours material that usually have more than 1 route into one linear story. This is where most studio production flops.
-And there's the problem with multiple heroines VNs like To Heart 2 and Comic Party. Most of the studios will keep in mind to actually spread the story to far so that every heroine has their own episode, resulting in a very thin story. And to makes things worst they never gave a proper ending.
-And there's also the "Make it into a ecchi anime" Syndrome, like Maji de Watashi ni Koishinasai
Ones that were really good when compare to the original:
Yosuga no Sora : Like you said, it's like the game. With it's omnibus style story, we can actually enjoy "ALL" the routes individually.
Amagami SS : Same as Yosuga no Sora, it uses an omnibus system. But the story is purely romance.
Steins;Gate :It sticks very closely to the original script which is already great to begin with, so the result is a great anime.
Other than the ones that I mention it's usually just so-so or just straight out a horrible adaptation.
Honestly, mostly the ones you listed as bad, was originally good as a VN. There's a reason why I use a character from Comic Party as a Avatar for the rest of my life. lol
Tsukihime, the original VN is indeed very bloody. Too bad you can't like Clannad/Kanon/Air
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No, the anime doesn't ruins the original VN. It will probably just ruin your motivation and trust.
The original VNs are already released way ahead of the anime adaptation so there's no way the anime will ruin the VN that's already well received before hand.
They don't ruin Visual Novels. The anime is pretty much always inferior to the VN. I think understanding that would help lead you to an understanding that you shouldn't expect as much from the anime. I believe Majikoi is a perfect example. Playing through the visual novel it had lots of story, very dramatic parts, as well as hilarious parts. Not to mention the H-scenes. When I watched the anime of Majikoi. It was focused almost entirely on the comedy. The drama of the series was left out. And of course there was no sex either. However I still enjoyed watching it. I am not about to go and say that the anime ruined the visual novel. It did not portray it to its fullest extent that is true. But I feel we should not let that deter us from playing the visual novels. As far as I have learned the original source material is always the best. If a series was originally a visual novel then the visual novel will be better then any anime or manga adaptations. If the series was originally a anime then the anime is better.