Black hat optimization is self-defeating
If content is the bread of Internet marketing, then search engine optimization is the butter that draws traffic to the content. There are ethics to be considered in the practice of SEO, and most of that covers SEO strategies that fall under either white hat or black hat optimization. Optimization techniques that are considered unethical are put under the black hat category, along with all the demerits placed upon them by search engines such as Google. Black hat optimization should be avoided to prevent search engines from imposing penalties on perpetuators.
The techniques that qualify under black hat optimization are typically, but not limited to, violating search engine rules and regulations, causing poor user experience to visitors either intentionally or not, and grabbing the attention of search engine users and spiders through visual or non-visual forms. These techniques were once considered to be white hat, until people started using them unethically to the point of being ostracized. It has to be noted that while black hat optimization techniques are in fact effective in achieving higher ranking, it does so only at a limited time.
One of the most common forms of black hat optimization is spamming. People resort to posting their comments in many different websites without due approval of the website owners, or duplicating their content and posting it several times over in their own website. Not only is this unattractive to search engines, but it also creates poor user experience for visitors who are looking for meaningful content.