All SEO comes down to 2 factors: 1) search engines; and 2) humans--
The “Do”s and “Don’t”s of SEO | lonelybrand: ". . . Keyword density could easily be the death of your content marketing strategy. Although most people and brands have abandoned this technique, I still occasionally stumble across a keyword density offender. What keyword density lovers fail to realize is not only does it make the content difficult to read, it makes the reader doubt the authority and expertise of the writer. Rather than jamming as many instances of a keyword or keyword phrase that you can in hopes of ranking higher, focus on creating natural sounding, informative and authoritative content focused around that keyword topic. Writing for search engines is so five years ago. Instead, create content with your target audience in mind — content that appeals to them in its tone, presentation and subject matter (not just keyword count). A search engine can’t really recognize your expertise, but a reader (a potential customer!) can, and will return to you regularly once that level of trust is established. . . ."
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