I prefer anime to manga. Here are my reasons:
1. Anime is a lower and less artistic medium than manga. This is because anime involves more elements and labour than manga which means that it's far more difficult to make an anime "perfect" than a manga, which is far more limited in its elements. The effect this ends up having is that manga ends up being the preferred medium for storytellers with deep and serious stories, wheras anime tends to be preferred by storytellers whose main goal is simply to create entertainment. I generally prefer stories that focus on being entertaining rather than those who aim to be some kind of magnum opus.
2. Since creating anime involves so much labour that conversely also keeps the riff-raff out, which means the average anime ends up having significantly more substance than the average manga.
3. Being a Film/TV medium anime has to focus on clarity above all else, which makes anime easier to consume. A detailed manga page can take several minutes to digest.
4. Anime is designed to be enjoyed by several people at a time whereas manga is designed to be read by one person at a time. I think stories can be more interesting when others are involved as you get to see their reaction and not only your own.
5. Many anime series and movies have good music. Listening to a soundtrack can be a way to remember an anime's story and carry it with you in your daily life. The only way you can revisit a manga is by re-reading it which takes more time and effort.
I do read manga as well though. Sometimes it is fun to engage with those magnum opus-style stories. Stories that intend to be more intimate or complex are often more effectively expressed in manga or books. Horror stories in particular tend to work better as manga or books in my opinion. But all in all I generally prefer anime to manga.
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