If the blogger promotes on it’s blog products and services that are of high quality and meets their demands and if he is honest about the benefits and features of things he promotes this trust will grow even more. On the other hand if the blogger is misleading his readership with a sole purpose to sell products and make money this trust can be broken..
Great advantage that blogs have over other websites is that blogs are focused on particular topic. There are blogs that are about healthy living, blogs about entertainment such as movies, music or video games, blogs about sports etc. Reader who come to certain blog come to read about what they like hence traffic they receive is targeted, which can be used to great advantage by the blogger if he promotes something related to the interest of his readers. On a blog abot movies you can promote for instance a subscription for Netflix or Blockbuster, Blogs about health and wellness can make promoting products such as herbal supplements and diet pills very lucrative. Audience visiting a blog about video games will be interested in buying gaming consoles or games.
Truth is affiliate marketing does work well on blogs. The traffic blog receives is targeted, and even more the visitors trust the blogger and they likely will buy what he recommends them. If they cant choose between products to buy, the recommendation from the blogger will tip the scale into buying the products he recommends/promotes.