Read below for a snippet.
SEO, or Search Engine Optimization is often misunderstood as something that happens overnight. “Optimizing” a website for the top search engines, isn’t a process that can be perfected in one sitting, but is a process that takes weeks and months to produce quality results.
In order for the search engines to give your site a good organic ranking, you must optimize your site to fulfill the major requirements of strong SEO. Things like writing quality, relevant content, keyword-rich title tags, correct length meta-descriptions, alt text for images, eliminating duplicate content and even your collection of links, takes time to cultivate into an A game plan. Plus, the search engines crawl and re-crawl your site forming a historic record of your site checking for things like consistency, frequent updates, and overall site strength. This means that SEO is never a "set it and forget it" strategy...
You can read the full post, SEO: A Marathon not a Sprint , over on the Sells Agency Blog.