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).
One thing Google has indicated it likes to do is penalize sites or stores or companies that consistently have poor reviews, so if you have many poor reviews, in time Google is going to figure out not to show your site in their rankings because Google doesn’t want to show those sites to their searchers. So prove to Google’s algorithm that you are trustworthy. Get other highly authoritative websites to link to you. Get newspaper articles, get industry links, get other trusted sites to link to you: partners, vendors, happy customers—get them to link to your website to show that you are highly credible and trustworthy.
While Google is on record as stating these quality raters do not directly influence where you rank (without more senior analysts making a call on the quality of your website, I presume?) – there are some things in this document, mostly of a user experience nature (UX) that all search engine optimisers and Webmasters of any kind should note going forward.
QUOTE: “Starting April 21 (2015), we will be expanding our use of mobile-friendliness as a ranking signal. This change will affect mobile searches in all languages worldwide and will have a significant impact in our search results. Consequently, users will find it easier to get relevant, high-quality search results that are optimized for their devices”. GOOGLE

How do you figure out what keywords your competitors are ranking for, you ask? Aside from manually searching for keywords in an incognito browser and seeing what positions your competitors are in, SEMrush allows you to run a number of free reports that show you the top keywords for the domain you enter. This is a quick way to get a sense of the types of terms your competitors are ranking for.
What about other search engines that use them? Hang on while I submit my site to those 75,000 engines first [sarcasm!]. Yes, ten years ago early search engines liked looking at your meta-keywords. I’ve seen OPs in forums ponder which is the best way to write these tags – with commas, with spaces, limiting to how many characters. Forget about meta-keyword tags – they are a pointless waste of time and bandwidth.
Basically, SEO keyword research should be an ongoing and ever-evolving part of your job as a marketer. Old keywords need to be reevaluated periodically, and high-volume, competitive keywords (or “head” keywords, as opposed to long-tailed keywords) can often be usefully replaced or augmented with longer, more specific phrases designed not to bring in just any visitor but exactly the right visitors. (Who visits your site – particularly if they’re people who are actively looking for your services – is at least as important as how many people visit.)
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