Banner blindness is a well-known term in the online marketing world. Since the first advertisement, a lot of research has been done into the effect of banners. When people see to much of the same kind of banners they get “banner blind”. So for your campaign it’s really important to try new styles and create more than 1 banner for your avertisment. Otherwise your campaign will slowly “die” and the CTR with in the end the CR goes down.