Glass on the phone has a slight curve to it on the edges, the screen protector doesn't entirely cover and adhere to the screen because of this. I expect over time dust and dirt to build up along the edges.
I didn't think I was that hard on my phone however, I don't seem to get more than a year out of the BodyGuardz glass screen protectors before they break. My phone is also in a BodyGuardz protective case so that doesn't seem to make a difference. I own and operate a small manufacturing company and am out on the floor all day so it is a sometimes heavy duty environment and drops happen. The for sure bet with BodyGuards is the lifetime guarantee. Never any problem with sending the broken screen saver in and having it replaced. Four Stars on the protector but definitely Five Stars on the guarantee.