Kairo (aka pulse) is suppose to be scary. its suppose to give you the feeling of eternal isolation. for me, however, it was mostly tedious with some moments that kept me watching. most often it felt like i kept watching hoping it would get better. thats not a good sign and of course it didn't change style at any point. its far from bad but nothing i'd run out to watch again.
i'd suspect some people will find this type of slow psychological horror more appealing, and perhaps i was just not in the mood for it when i saw it. but honestly it nearly bored me.