There are several other articles on this site discussing source material translated into film adaptations. And while there are many different mediums to draw from, I would like to focus on the making of Manga (Japanese comic style) to Anime, to which there are some pros, but overall I would like to argue that there much more cons.
There are many different styles and genres in the Manga world, but I’m going to be using one of the broadest terms, Shounen, as an example. In a shounen manga, the main focus is on the action, adventure and plot, often times gory, violent, and it is often directed to a male audience. Examples of this genre are Inuyasha, Yu Yu Hakasho, Bleach, and Naruto.
There are many aspects of Shounen manga that may not make sense in reality, but for a still image comic, they are necessary so the at reader can understand what is happening in the page. It is often that the reader is given insight to what the character on the page is thinking through explicit, often repetitive dialogue, to reinforce the actions the reader has to imagine. Sometimes the plot can get convoluted in the black and white still images, and the repetition can be comforting. In anime, this images are in color and animated. The constant repetition of facts, from both mental processes and verbal reiteration, makes the characters seem duller than they need to be. Instead of being helpful to the plot in the manga, repetition becomes annoying and useless.
In Japanese manga, it is common place to have very large, ornate, elaborate fighting moves, visually stimulating even as a black and white stills. The attacks often take more than page, and their after effects several more. They are very impressive, but one of the draw backs is that all of these elaborate moves come with long elaborate names. Again, this isn’t a big problem in manga, because it often helps the reader visualize what is going on beyond the page. In Anime, however, this practice has always bothered the hell out of me. Anyone with any martial arts training will tell you to never advertise what you are going to do to the opponent. When put into animation, it just emphasizes how awkward and unnecessary the long name of the attack is, especially after the fifth time seeing it used in the exact same way. The characters are always so shocked when their attack is dodged or guarded or do no damage, while the audience is yelling at the tv/computers. It’s even worse when it does land perfectly because most people are scratching their heads and asking ‘why is this villain so dumb?’
Another trop that goes hand in hand with long drawn out attacks is the in depth descriptions for what the attack can do and how exactly it works. This is something that one-shot villains are prone to, people that are only going to be in one battle. Again, slightly necessary in still images, but one of the most annoying tropes preformed in animes. It always leads to the villain’s downfall and always makes even the most intelligent opponents seem dimwitted. The suspension of disbelief façade is broken apart with a sledge hammer.
These three aspects that are common in both Shounen manga and anime. While being two separate mediums, are closely interwoven. There are details and clichés present in manga that are sometimes necessary to clarify and enhance the visual impact of the manga. When the producers look at a popular manga and want to put if to film, the worse thing that can happen, ironically enough, is to just copy and paste the manga into an anime, it’s too distinct of a separation of a medium.
This clip was grabbed to illustrate that fighting names are long, loud, and exaggerated, but shows one of the other problems with shouting the name of an attack. At :33 the scene of the blades of blood is used, and of course the lady Inuyasha is attacking is hit by it, but then, not five seconds later, she is fooled by the very same attack and exact same way!