SEO may generate an adequate return on investment. However, search engines are not paid for organic search traffic, their algorithms change, and there are no guarantees of continued referrals. Due to this lack of guarantees and certainty, a business that relies heavily on search engine traffic can suffer major losses if the search engines stop sending visitors. Search engines can change their algorithms, impacting a website's placement, possibly resulting in a serious loss of traffic. According to Google's CEO, Eric Schmidt, in 2010, Google made over 500 algorithm changes – almost 1.5 per day. It is considered a wise business practice for website operators to liberate themselves from dependence on search engine traffic. In addition to accessibility in terms of web crawlers (addressed above), user web accessibility has become increasingly important for SEO.
A poor 404 page and user interaction with it, can only lead to a ‘poor user experience’ signal at Google’s end, for a number of reasons. I will highlight a poor 404 page in my audits and actually programmatically look for signs of this issue when I scan a site. I don’t know if Google looks at your site that way to rate it e.g. algorithmically determines if you have a good 404 page – or if it is a UX factor, something to be taken into consideration further down the line – or purely to get you thinking about 404 pages (in general) to help prevent Google wasting resources indexing crud pages and presenting poor results to searchers. I think rather that any rating would be a second order scoring including data from user activity on the SERPs – stuff we as SEO can’t see.
Forget whether or not to put your keyword in it, make it relevant to a searcher and write it for humans, not search engines. If you want to have this 20-word meta description which accurately describes the page you have optimised (for one or two keyword phrases) when people use Google to search, make sure the keyword is in there. There is more likelihood it will be used by Google as your snippet description in SERPs.
QUOTE: “The average duration metric for the particular group of resources can be a statistical measure computed from a data set of measurements of a length of time that elapses between a time that a given user clicks on a search result included in a search results web page that identifies a resource in the particular group of resources and a time that the given user navigates back to the search results web page. …Thus, the user experience can be improved because search results higher in the presentation order will better match the user’s informational needs.” High Quality Search Results based on Repeat Clicks and Visit Duration
QUOTE: “high quality content is something I’d focus on. I see lots and lots of SEO blogs talking about user experience, which I think is a great thing to focus on as well. Because that essentially kind of focuses on what we are trying to look at as well. We want to rank content that is useful for (Google users) and if your content is really useful for them, then we want to rank it.” John Mueller, Google 2016
A lot of optimisation techniques that are in the short term effective at boosting a site’s position in Google are against Google’s guidelines. For example, many links that may have once promoted you to the top of Google, may, in fact, today be hurting your site and its ability to rank high in Google. Keyword stuffing might be holding your page back. You must be smart, and cautious, when it comes to building links to your site in a manner that Google *hopefully* won’t have too much trouble with, in the FUTURE. Because they will punish you in the future.
For example, let’s say you were running the website of an online pet store. You might be wise to create one keyword grouping for all your dog-related products, then one for all of your parakeet-related projects, etc. The next step would be to segment each individual group into smaller subgroups (parakeet cages, parakeet toys, parakeet snacks) and then even smaller groups for each type of product (low-fat parakeet snacks, luxury parakeet snacks… you get the idea). Now your pet store can create individual pages optimized for each small keyword group.