Backlinks are important for a number of reasons. The quality and quantity of pages backlinking to your website are some of the criteria used by search engines like Google to determine your ranking on their search engine results pages (SERP). The higher you rank on a SERP, the better for your business as people tend to click on the first few search results Google, Bing or other search engines return for them.
So, now we're getting to backlinks that have relatively little, or even negative value. The value of web directories has diminished dramatically in recent years. This shouldn't come as a surprise. After all, when was the last time that you used a web directory to find anything, rather than just doing a Google search? Google recognizes that directories don't have any real world worth, and so they don't accord much value to backlinks on them. But there is an exception to this rule. Submitting your website to local, industry-specific and niche directories can net you worthwhile backlinks. But if you can't imagine a circumstance where someone would use a certain directory, then it's probably not worth your time.
While ordinary users were not that interested in pages' scores, SEOs of a different caliber felt that this was a great opportunity to make a difference for their customers. This obsession of SEOs with PageRank made everyone feel that this ranking signal is more or less the only important one. In spite of the fact that pages with a lower PR score can beat those with a higher score! What did we receive then, as a result?