If you were using a static site to add content from multiple authors, each author would have to download the pages from the server to their computer first, update them, then upload them back to the server. This would be very time consuming and could generate a lot of errors.
Create Search Engine Friendly Pages
The separation of content from design allows you to easily include keywords in the URL of each page. If the title of your article was “Content Management System Benefits” your URL would be written as:
http://www.domainname.com/content-management-system-benefits Some CMS sites automatically generate the correct meta tags for each web page which would help them to spidered by the search engines.