Site architecture is the way every page of your website is linked to every other page. It’s the way people and search engines navigate your website, and it’s equally important to both of them. You want both people and search engines to be able to easily find what they’re looking for.
Believe it or not, a poor site architecture can completely kill off rankings, traffic and even conversions. The reasons for this are many. First, if there’s no way for a search engine to access much of the content of a site because the only way to reach the “meat” is through search forms that need to be submitted, search engines won’t find or index most of it.