The phrase, "Affiliates are an extended sales force for your business", which is often used to explain affiliate marketing, is not completely accurate. The primary difference between the two is that affiliate marketers provide little if any influence on a possible prospect in the conversion process once that prospect is directed to the advertiser's website. The sales team of the advertiser, however, does have the control and influence up to the point where the prospect either a) signs the contract, or b) completes the purchase.
Word of mouth communications and peer-to-peer dialogue often have a greater effect on customers, since they are not sent directly from the company and are therefore not planned. Customers are more likely to trust other customers’ experiences. Examples can be that social media users share food products and meal experiences highlighting certain brands and franchises. This was noted in a study on Instagram, where researchers observed that adolescent Instagram users' posted images of food-related experiences within their social networks, providing free advertising for the products.
Sponsored search (also called sponsored links, search ads, or paid search) allows advertisers to be included in the sponsored results of a search for selected keywords. Search ads are often sold via real-time auctions, where advertisers bid on keywords.:118 In addition to setting a maximum price per keyword, bids may include time, language, geographical, and other constraints.:118 Search engines originally sold listings in order of highest bids.:119 Modern search engines rank sponsored listings based on a combination of bid price, expected click-through rate, keyword relevancy and site quality.
According to a paper by Duncan Watts and colleagues entitled: "Everyone's an influencer", the most common risk in viral marketing is that of the influencer not passing on the message, which can lead to the failure of the viral marketing campaign. A second risk is that the influencer modifies the content of the message. A third risk is that influencers pass on the wrong message. This can result from a misunderstanding or as a deliberate move.