The social media landscape is constantly evolving. New networks rise to prominence (e.g. Snapchat), new technology increases user participation and real-time content (e.g. Periscope) and existing networks enhance their platform and product (e.g. Facebook,Twitter, Pinterest and Instagram launching ‘buy’ buttons). Organic reach is also shrinking as the leading networks ramp up their paid channels to monetise platform investment.
Search engines may penalize sites they discover using black hat methods, either by reducing their rankings or eliminating their listings from their databases altogether. Such penalties can be applied either automatically by the search engines' algorithms, or by a manual site review. One example was the February 2006 Google removal of both BMW Germany and Ricoh Germany for use of deceptive practices. Both companies, however, quickly apologized, fixed the offending pages, and were restored to Google's list.
Additionally, there are many situations where PPC (a component of SEM) makes more sense than SEO. For example, if you are first launching a site and you want immediate visibility, it is a good idea to create a PPC campaign because it takes less time than SEO, but it would be unwise to strictly work with PPC and not even touch search engine optimization.
Black hat SEO refers to the practice of trying to trick the search engines into giving you higher rankings by using unethical tactics, such as buying links. The risk is just too great. Even if you enjoy a temporary boost in rankings due to black hat tactics, it’s likely to be short lived. Google is getting better and better at spotting dirty tricks and sooner or later the progress you made will be wiped out by an algorithm update, or worse, your site will get removed from the index altogether.
At our agency, we work with sites of varying sizes, from very large to quite small, and recently, we have noticed a trend at the enterprise level. These sites aren’t relying as much on Google for traffic any more. Not only are they not relying on Google traffic, but also, the sites are getting less than 10 percent (or slightly more) of their organic traffic from the search giant.