There is a change coming on the internet that mimics search as it really was in the early days. In the very beginning, search was developed to find answers and there were more people with questions than truly authoritative sites with answers. Authorities were identified by a combination of competent, well-constructed content and testimonial-grade inbound links (essentially a trusted, quality link system).
This led to a culture of link-building and eventually deceptive link spamming, which eroded and eventually undermined the concept of trusted links. It can be really difficult to identify a purchased link from an earned testimonial-grade link. Simply put, spammer link camouflage is just too good that it fools an unaware internet user many times.