The world is mobile today. Most people are searching on Google using a mobile device. The desktop version of a site might be difficult to view and use on a mobile device. As a result, having a mobile ready site is critical to your online presence. In fact, starting in late 2016, Google has begun experiments to primarily use the mobile version of a site's content42 for ranking, parsing structured data, and generating snippets.
It helps to improve your ranking for certain keywords. If we want this article to rank for the term ’SEO basics’ then we can begin linking to it from other posts using variations of similar anchor text. This tells Google that this post is relevant to people searching for ‘SEO basics’. Some experts recommend varying your anchor text pointing to the same page as Google may see multiple identical uses as ‘suspicious’.
QUOTE: “common with forums is low-quality user-generated content. If you have ways of recognizing this kind of content, and blocking it from indexing, it can make it much easier for algorithms to review the overall quality of your website. The same methods can be used to block forum spam from being indexed for your forum. Depending on the forum, there might be different ways of recognizing that automatically, but it’s generally worth finding automated ways to help you keep things clean & high-quality, especially when a site consists of mostly user-generated content.” John Mueller, Google
Naturally, business owners want to rank for lots of keywords in organic listings with their website. The challenge for webmasters and SEO is that Google doesn’t want business owners to rank for lots of keywords using auto-generated content especially when that produces A LOT of pages on a website using (for instance) a list of keyword variations page-to-page.
QUOTE: “Some Low-quality pages have adequate MC (main content on the page) present, but it is difficult to use the MC due to disruptive, highly distracting, or misleading Ads/SC. Misleading titles can result in a very poor user experience when users click a link only to find that the page does not match their expectations.” Google Search Quality Evaluator Guidelines 2015
Users will occasionally come to a page that doesn't exist on your site, either by following a broken link or typing in the wrong URL. Having a custom 404 page30 that kindly guides users back to a working page on your site can greatly improve a user's experience. Your 404 page should probably have a link back to your root page and could also provide links to popular or related content on your site. You can use Google Search Console to find the sources of URLs causing "not found" errors31.
QUOTE: “The purpose of a page is the reason or reasons why the page was created. Every page on the Internet is created for a purpose, or for multiple purposes. Most pages are created to be helpful for users, thus having a beneficial purpose. Some pages are created merely to make money, with little or no effort to help users. Some pages are even created to cause harm to users. The first step in understanding a page is figuring out its purpose.” Google Search Quality Evaluator Guidelines 2019
However, if possible, I would like you to expand a bit on your “zombie pages” tip..we run a site where are definitely enough pages to delete (no sessions, no links, probably not even relevant with the main theme of the site, not even important for the architecture of the site)..Nonetheless, I am not very sure what is the best technical decision for these pages…just deleting them from my CMS, redirecting (if there is a relevant alternative) or something else? Unindex them on Search console? what response code they should have? ..