Japanese, Taiwanese, and Korean directors have used up their ideas

The titles tell it all. It seems that most ( well not most but some) of the upcoming dramas and already aired dramas are based on manga. Even though these dramas have high rating like Goong/Palace/Princess hours, why can’t the directors come with new ideas. to watch these dramas is like rereading the manga or in some cases rewatching the anime. It’s not like i’m complaining or anything. i have love watching goong, hana kimi, peach girl, princess princess D, devil beside you, ISWAK, full house, ect.. I’m just trying to prove the directors have used up their ideas. Some of the dramas doesn’t exactly follow the manga except the Taiwanese directors who follow every single details of the manga which is so boring. Every time i watch the drama , i alway wonder why are the directors remaking the manga? is it because of the fans if so why do the fans want to watch these manga in to dramas ?

pics of the drama that are based on the manga