There are numerous not so advisable ways to optimize your website on the search engines. Some of such ways are quite infamous too and often very susceptible to the algorithmic updates of Google. On one point probably all the webmasters will agree that Black hat SEO should be avoided for the benefit of the site in the long run.
Anchor Text for Link Building: Having the exact keyword as your anchor text cannot earn you a good position in the search engine anymore. In fact, the Penguin update has landed many sites with anchor texts matching completely with their keywords. This kind of disrepute has made it very difficult for them to recover in the near future.
Low Quality Content Affects Link Building: Mindless link building can harm your website in more possible ways than doing anything beneficial for it. Inbound links from sites with poor contents, unnecessary ads and often-low traffic influx despite having good quality content and ads can avert links from sites with high PR. Moreover, this link building procedure has its own limitations and it cannot work for long. In the long run, it is only going to hurt the search rankings of the site.
Overused Articles: Article syndication is a very old and poor system of optimizing a website. This practice still works for short-term benefit of a website. However, it is never advisable for the long term stability of search rankings of a site. Article syndication allows one particular article to be submitted to multiple article submission sites, which in turn can only lower down credibility of its owner. Sometimes, site owners prefer spinning multitude of different articles out of one piece of content. This procedure often ends up yielding write-ups with grammatical errors and poor quality of sentences. It is needless to say that any habit of this format has never done any good to any website.
All the above mentioned black hat SEO practices and several other like these cannot ensure sustained SERPs or higher search engine rank for a long term to websites. There is no point risking the position of your website’s rank for short-term benefit. Avoiding black hat practices also help you avoiding being penalized by Google.