Having a blog is a serious time investment, and every word is worth it. Here's why.
Relevant keywords / number and placement of keywords
Blogging enables you to mention multiple keywords that can be relevant to a search. Every time you blog, you increase the number of times the keywords are mentioned. Often times keywords will end up in the title of your blog, increasing their importance in the Google ranking algorithm and making your site more likely to be returned in the results of a search.
Number of pages on a website
Having a lot of pages indicates to Google that you have a lot of information. Since Google’s mission is to connect users with the information they seek, having a blog positions you as an industry expert whose site is valuable. Each time you write a blog post, a page for that post is automatically created, increasing the number of pages on your site and increasing your Google ranking.
Frequency of site changes
Google wants to provide its users with the most up-to-date information. The logic is, the more often you change your site, the more current your information is. Google’s crawlers will re-visit your website and, if you have made edits since the last time it was crawled, the crawler will make a note of it and return more frequently. If you continually update your site, it will be crawled more and more often, and the information you post will be catalogued closer to real-time. Every blog post counts as an update to your site, and will increase your search engine ranking, as well as the frequency of your crawling.