Length of site domain registration; (I don’t see much benefit ON IT”S OWN even knowing “Valuable (legitimate) domains are often paid for several years in advance, while doorway (illegitimate) domains rarely are used for more than a year.”) – paying for a domain in advance just tells others you don’t want anyone else using this domain name, it is not much of an indication that you’re going to do something Google cares about).
Sometimes, Google turns up the dial on demands on ‘quality’, and if your site falls short, a website traffic crunch is assured. Some sites invite problems ignoring Google’s ‘rules’ and some sites inadvertently introduce technical problems to their site after the date of a major algorithm update and are then impacted negatively by later refreshes of the algorithm.

"I wanted to thank you guys for everything you've done for my company. When I first went to Curt for help about a 1.5 years ago, I was a very tiny company. We're now doing about 1500 jobs a month, and I give a lot of credit to you guys for the exposure. It's been life changing for me. I was working 12 hour days, 7 days a week for 2 years. I am finally able to back off some because I can afford office help as well. Thanks for being so great at what you do. I still don't know what that is exactly, but thanks for doing it so well."
Put differently, to be phenomenally successful, we seek not to take static content and try to pry greater results from it; instead, we leverage the existing needs of the users, and use that knowledge to help us create the best possible user experience. That, in turn, will be rewarded with higher rankings, greater traffic, and a higher ROI from our marketing efforts.
QUOTE: “7.4.3 Automatically ­Generated Main Content Entire websites may be created by designing a basic template from which hundreds or thousands of pages are created, sometimes using content from freely available sources (such as an RSS feed or API). These pages are created with no or very little time, effort, or expertise, and also have no editing or manual curation. Pages and websites made up of auto­generated content with no editing or manual curation, and no original content or value added for users, should be rated Lowest.” Google Search Quality Evaluator Guidelines 2017

Use the Keyword Planner to flag any terms on your list that have way too little (or way too much) search volume, and don't help you maintain a healthy mix like we talked about above. But before you delete anything, check out their trend history and projections in Google Trends. You can see whether, say, some low-volume terms might actually be something you should invest in now -- and reap the benefits for later.
Most people search on mobile devices - You don't need statistics to show you that in the past few years the online mobile market has exploded, overtaking desktops years ago. Optimizing websites for mobile browsers is critical if you want to rank well in search engine results pages. If you’re unsure how your website measures up, enter your site’s URL in Google's Mobile-Friendly Test.
As an Internet marketing strategy, SEO considers how search engines work, the computer-programmed algorithms that dictate search engine behavior, what people search for, the actual search terms or keywords typed into search engines, and which search engines are preferred by their targeted audience. SEO is performed because a website will receive more visitors from a search engine the higher the website ranks in the search engine results page (SERP). These visitors can then be converted into customers.[4]

QUOTE: “Content which is copied, but changed slightly from the original. This type of copying makes it difficult to find the exact matching original source. Sometimes just a few words are changed, or whole sentences are changed, or a “find and replace” modification is made, where one word is replaced with another throughout the text. These types of changes are deliberately done to make it difficult to find the original source of the content. We call this kind of content “copied with minimal alteration.” Google Search Quality Evaluator Guidelines March 2017

An SEO technique is considered white hat if it conforms to the search engines' guidelines and involves no deception. As the search engine guidelines[18][19][52] are not written as a series of rules or commandments, this is an important distinction to note. White hat SEO is not just about following guidelines but is about ensuring that the content a search engine indexes and subsequently ranks is the same content a user will see. White hat advice is generally summed up as creating content for users, not for search engines, and then making that content easily accessible to the online "spider" algorithms, rather than attempting to trick the algorithm from its intended purpose. White hat SEO is in many ways similar to web development that promotes accessibility,[53] although the two are not identical.
QUOTE: “Shopping or financial transaction pages: webpages which allow users to make purchases, transfer money, pay bills, etc. online (such as online stores and online banking pages)…..We have very high Page Quality rating standards for YMYL pages because low-quality YMYL pages could potentially negatively impact users’ happiness, health, or wealth.“
So: how to proceed? On the one hand, SEO best practices recommend that you include relevant keywords in a number of high-attention areas on your site, everywhere from the titles and body text of your pages to your URLs to your meta tags to your image file names. On the other hand, successfully optimized websites tend to have thousands or even millions of keywords. You can't very well craft a single, unique page for every one of your keywords; at the same time, you can't try to cram everything onto a handful of pages with keyword stuffing and expect to rank for every individual keyword. It just doesn't work that way.