Ezinearticles.com, although hit by the new Google algorithm, it is a great source of highly targeted traffic. The bounce rate of visitors I get from EZA is always less than 20%! Choosing a good keyword for an article can result in incredible amounts of traffic. I have been receiving a lot of traffic from a single well written article for a year and a half now!
Otherwise you might end up polluting your website’s traffic. The pages filled with obsolete or low quality content aren’t useful or interesting to the visitor. Thus, they should be pruned for the sake of your website’s health. Low quality pages may affect the performance of the whole site. Even if the website itself plays by the rules, low-quality indexed content may ruin the organic traffic of the whole batch.
Let’s say that you are selling dog food. And most likely you will want the best traffic possible on the keyword “dog food”. Creating/building/earning all of your links with the same anchor text will get you in trouble. If you are having 600 links from which 400 use the anchor “dog food”, you might be facing a problem; it will surely raise a red flag to the search engines. And we all know what search engines do when they are getting these kinds of alarms: they begin applying penalties and move your websites so far from reach of the user that you will not be even listed in top 100. 

The term “organic traffic” is used for referring to the visitors that land on your website as a result of unpaid (“organic”) search results. Organic traffic is the opposite of paid traffic, which defines the visits generated by paid ads. Visitors who are considered organic find your website after using a search engine like Google or Bing, so they are not “referred” by any other website.