The criteria and metrics can be classified according to its type and time span. Regarding the type, we can either evaluate these campaigns "Quantitatively" or "Qualitatively". Quantitative metrics may include "Sales Volume" and "Revenue Increase/Decrease". While qualitative metrics may include the enhanced "Brand awareness, image and health" as well as the "relationship with the customers".
Another disadvantage is that even an individual or small group of people can harm image of an established brand. For instance Dopplegnager is a term that is used to disapprove an image about a certain brand that is spread by anti-brand activists, bloggers, and opinion leaders. The word Doppelganger is a combination of two German words Doppel (double) and Ganger (walker), thus it means double walker or as in English it is said alter ego. Generally brand creates images for itself to emotionally appeal to their customers. However some would disagree with this image and make alterations to this image and present in funny or cynical way, hence distorting the brand image, hence creating a Doppelganger image, blog or content (Rindfleisch, 2016).
Affiliate marketing overlaps with other Internet marketing methods to some degree, because affiliates often use regular advertising methods. Those methods include organic search engine optimization (SEO), paid search engine marketing (PPC – Pay Per Click), e-mail marketing, content marketing, and (in some sense) display advertising. On the other hand, affiliates sometimes use less orthodox techniques, such as publishing reviews of products or services offered by a partner.