@Xiogenes
Thats just the very basic difference between manga & novel man.
Go to novel for the story, go to manga for the visual.
Its just impossible to fit everything into the drawing, making them to cut many details.
On the other hand, they need to accentuate their main value of the "visual", which sometimes taking up more allocated panel, further deviate them from the novel.
*At least for most of the case