Over-optimization occurs when a website's elements are present in too high a proportion or too high in power for a given keyword phrase. Over-optimization yields poor search performance. An example of over-optimization would be the incessant use of keywords on your website, so that your keywords represent 50 percent of the total density of words on the page. Another example would be a website with 100 inbound links, all with the same exact anchor text. First-time SEO hobbyists tend to be ensnared by over-optimization as they zealously pursue the new elements of SEO that they learn; they stuff keywords into title tags, meta tags, body text, and secure links all with the same anchor text.

Over-optimization is difficult to quantify, and can be difficult to detect and repair. The best way to think about over-optimization is that websites should never be too perfect. Remember, a search engine ultimately must employ mathematics to its ranking criteria. It's easy for a search engine to mathematically determine that a page with a keyword density—keywords as a percentage of total words on the page—exceeding 8 percent is attempting to game the algorithm and therefore should not be ranked.

Thinking about over-optimization in this way, repetition is often the main culprit. To avoid over-optimization you'll need to be vigilant to watch for excessive repetition of terms in the main elements of a website and in inbound links. In other words, just do good writing and the rest will follow naturally. You wouldn't keep repeating yourself in good writing.