For example, if the humidity is high, the wallpaper is easy to make an exception or rot. After all, wallpaper is made of organic substances such as plant fibers. Besides, there are spots on your wall. Wallpaper is easily damaged when you use it. Even if the wall paint is painted again, the moisture on your wall will still damage the wallpaper.
There are other requirements for the use of wallpaper, such as indoor ventilation can not be frequent, otherwise it is easy to make wallpaper edge; Wallpapers are not easy to install in places like balconies and exposed to the sun; etc