The first major profit center for Google was (and remains) providing relevant search results on a web browser to people online based on their particular queries (or “online searches”).
The value of a search engine algorithm is its ability to find and rank relevant content that people find useful so they keep coming back to the platform for future searches.
To be effective at finding and ranking relevant content among millions of websites across the world, search engine crawlers must find and then understand a webpage’s content and context to effectively match search queries with relevant results that keep people coming back for more.
A sitemap allows webmasters to communicate to search engine crawlers what pages they should pay attention to and index and also the hierarchy and various relationships of pages within your website.
Google does not see all pages on a website as carrying the same level of importance which is why your webpage hierarchy and updates are so important to communicate to Google – via their search engine crawlers.
For example, your site’s Homepage is much more valuable than your “Contact Us” page because of its content and hierarchical placement compared to other pages on your site.
If any page had to go down on your site, you would want it to be one of the least visited pages. Pages with the most traffic are the most valuable to your business.
Page depth becomes an important consideration when developing a website because communicating the hierarchy of each page on a site to search engine crawlers is necessary and important.
A general rule for page depth is three: any page on a website should be accessible within three clicks.
So, good structure, coupled with valuable and relevant content, increases your websites chances of ranking higher on SERPs.