It may be difficult to see in the picture to the right, but that exterior light has been wired with an extension cord. Unfortunately, this can sometimes be a common thing to see on a home inspection - but it is definitely unsafe.
First of all, an extension cord is made for temporary power to something that will not run continuously, and a light does not fall under that category. In addition to that, the wiring is not the proper gauge in this instance, and is also not properly protected. It is also not UV resistant enough and can break down. Critters chewing on it, sun damage, and the list goes on.
In short, never use an extension cord to wire anything permanent.
Devereaux Van Dyne, Certified Professional Home Inspector