There's no correct answer to this question. However, I have rarely seen a piece of fiction with more than about one in five ratio of dialogue to narrative that was worth reading. Dialogue is difficult to write well. But good dialogue also takes some effort to read well, because it exists on more than one level. On the other hand, weak dialogue is just tedious to plow through. Either way, dialogue is harder on the reader than narrative. Scripts are the exception, but scripts are not intended to be read so much as performed. The context surrounding the dialogue in a script is primarily filled in by the director.
Thanks, it's funny the thing i read on the web are completely the opposite, but they don't support their arguments.
Writing well is hard no matter what it is. There are no right answers that apply generally. Every story will demand for something different.
