Why Pay for Directory Links?
Links are an important factor considered by search engines to rank a site. Different methods are used for obtaining links one amongst them is buying links. Many of the search engine experts do not trust the results based on link buying there are others who use their technique to their maximum benefit.
It is believed that paid directory links are better for SEM purposes as opposed to text link advertising as the link are placed in the most appropriate category. These links are placed in relevancy to the site content.
Search engine spider is an algorithm. It crawls the site in question often and often to look for new content to related topics, fresh information and use that information to algorithmically produce the most relevant result. The many links on the site make it easy for the search engines to navigate your site. Each link to the site is checked to find relevancy, destination where the spiders are led and source if they are from "Trusted" or "Authority" site.