There are many people who create an amazing site with many graphics, with great information and a large menu structure, but once they are done with that initial project, they assume that this is going to be a “set it and forget it” kind of deal. Unfortunately, they end up seeing their website fall into obscurity and go down lower on the SEO ranks in just a matter of weeks.
The truth is that the only way to keep your website relevant and SEO friendly is to constantly come up with new material. You need to be posting new blogs or new article at least 3 to 5 times a week if you want to compete with others. Some site owners are posting daily and others even twice a day.