The reality in 2019 is that if Google classifies your duplicate content as THIN content, or MANIPULATIVE BOILER-PLATE or NEAR DUPLICATE ‘SPUN’ content, then you probably DO have a severe problem that violates Google’s website performance recommendations and this ‘violation’ will need ‘cleaned’ up – if – of course – you intend to rank high in Google.
Goals and Objectives. Clearly define your objectives in advance so you can truly measure your ROI from any programs you implement. Start simple, but don’t skip this step. Example: You may decide to increase website traffic from a current baseline of 100 visitors a day to 200 visitors over the next 30 days. Or you may want to improve your current conversion rate of one percent to two in a specified period. You may begin with top-level, aggregate numbers, but you must drill down into specific pages that can improve products, services, and business sales.
I do not obsess about site architecture as much as I used to…. but I always ensure my pages I want to be indexed are all available from a crawl from the home page – and I still emphasise important pages by linking to them where relevant. I always aim to get THE most important exact match anchor text pointing to the page from internal links – but I avoid abusing internals and avoid overtly manipulative internal links that are not grammatically correct, for instance..
Don’t be a website Google won’t rank – What Google classifies your site as – is perhaps the NUMBER 1 Google ranking factor not often talked about – whether it Google determines this algorithmically or eventually, manually. That is – whether it is a MERCHANT, an AFFILIATE, a RESOURCE or DOORWAY PAGE, SPAM, or VITAL to a particular search – what do you think Google thinks about your website? Is your website better than the ones in the top ten of Google now? Or just the same? Ask, why should Google bother ranking your website if it is just the same, rather than why it would not because it is just the same…. how can you make yours different. Better.
Either porn SC or Ads containing porn on non­Porn pages can be very distracting or even upsetting to users. Please refresh the page a few times to see the range of Ads that appear, and use your knowledge of the locale and cultural sensitivities to make your rating. For example, an ad for a model in a revealing bikini is probably acceptable on a site that sells bathing suits. However, an extremely graphic porn ad may warrant a Low (or even Lowest) rating.”
One concern we hear frequently is whether it is beneficial or harmful to repeat keywords. In other words, should we vary keywords (dog food, puppy food, and Purina) or repeat keywords (dog food reviews, dog food comparison, and dog food rankings.) The short answer is that the repetition is just fine, as long as the meaning of the phrase as a whole is sufficiently varied. In other words, dog food and dog food online are basically synonymous, and the content that one might expect to find associated with both keywords is the same. However, dog food reviews and dog food comparison indicate somewhat different content and therefore are appropriate to be used in tandem as keywords.
Yes, you need to build links to your site to acquire more PageRank, or Google ‘juice’ – or what we now call domain authority or trust. Google is a link-based search engine – it does not quite understand ‘good’ or ‘quality’ content – but it does understand ‘popular’ content. It can also usually identify poor, or THIN CONTENT – and it penalises your site for that – or – at least – it takes away the traffic you once had with an algorithm change. Google doesn’t like calling actions the take a ‘penalty’ – it doesn’t look good. They blame your ranking drops on their engineers getting better at identifying quality content or links, or the inverse – low-quality content and unnatural links. If they do take action your site for paid links – they call this a ‘Manual Action’ and you will get notified about it in Webmaster Tools if you sign up.
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.
After trying a lot (10+ years of experience) SE ranking stands out on top of others because it combines everything we need for our clients. We do only provide the client with rankings, but also with the potential traffic (and revenue) of those ranking when they hit top 3 in Google. The tool let us provide the client with in depth analysis of the technical stuff ánd a marketing plan tool, so we can set goals and follow a checklist of monthly activities. And to top it all off it’s fully whitelabel.
Companies that employ overly aggressive techniques can get their client websites banned from the search results. In 2005, the Wall Street Journal reported on a company, Traffic Power, which allegedly used high-risk techniques and failed to disclose those risks to its clients.[15] Wired magazine reported that the same company sued blogger and SEO Aaron Wall for writing about the ban.[16] Google's Matt Cutts later confirmed that Google did in fact ban Traffic Power and some of its clients.[17]
By 2004, search engines had incorporated a wide range of undisclosed factors in their ranking algorithms to reduce the impact of link manipulation. In June 2007, The New York Times' Saul Hansell stated Google ranks sites using more than 200 different signals.[26] The leading search engines, Google, Bing, and Yahoo, do not disclose the algorithms they use to rank pages. Some SEO practitioners have studied different approaches to search engine optimization, and have shared their personal opinions.[27] Patents related to search engines can provide information to better understand search engines.[28] In 2005, Google began personalizing search results for each user. Depending on their history of previous searches, Google crafted results for logged in users.[29]
In short, nobody is going to advise you to create a poor UX, on purpose, in light of Google’s algorithms and human quality raters who are showing an obvious interest in this stuff. Google is rating mobile sites on what it classes is frustrating UX – although on certain levels what Google classes as ‘UX’ might be quite far apart from what a UX professional is familiar with in the same ways as Google’s mobile rating tools differ from, for instance,  W3c Mobile testing tools.
In 1998, two graduate students at Stanford University, Larry Page and Sergey Brin, developed "Backrub", a search engine that relied on a mathematical algorithm to rate the prominence of web pages. The number calculated by the algorithm, PageRank, is a function of the quantity and strength of inbound links.[22] PageRank estimates the likelihood that a given page will be reached by a web user who randomly surfs the web, and follows links from one page to another. In effect, this means that some links are stronger than others, as a higher PageRank page is more likely to be reached by the random web surfer.
Early versions of search algorithms relied on webmaster-provided information such as the keyword meta tag or index files in engines like ALIWEB. Meta tags provide a guide to each page's content. Using metadata to index pages was found to be less than reliable, however, because the webmaster's choice of keywords in the meta tag could potentially be an inaccurate representation of the site's actual content. Inaccurate, incomplete, and inconsistent data in meta tags could and did cause pages to rank for irrelevant searches.[10][dubious – discuss] Web content providers also manipulated some attributes within the HTML source of a page in an attempt to rank well in search engines.[11] By 1997, search engine designers recognized that webmasters were making efforts to rank well in their search engine, and that some webmasters were even manipulating their rankings in search results by stuffing pages with excessive or irrelevant keywords. Early search engines, such as Altavista and Infoseek, adjusted their algorithms to prevent webmasters from manipulating rankings.[12]

QUOTE: “Google will now begin encrypting searches that people do by default, if they are logged into already through a secure connection. The change to SSL search also means that sites people visit after clicking on results at Google will no longer receive “referrer” data that reveals what those people searched for, except in the case of ads.
QUOTE: “In place of a pop-up try a full-screen inline ad. It offers the same amount of screen real estate as pop-ups without covering up any content. Fixing the problem depends on the issue you have for example if it’s a pop-up you’ll need to remove all the pop-up ads from your site but if the issue is high ad density on a page you’ll need to reduce the number of ads” Google, 2017
Google expects pages to “be edited, reviewed, and updated on a regular basis” especially if they are for important issues like medical information, and states not all pages are held to such standards, but one can expect that Google wants information updated in a reasonable timescale. How reasonable this is, is dependant on the TOPIC and the PURPOSE of the web page RELATIVE to competing pages on the web.

QUOTE: “Over time, we’ve seen sites try to maximize their “search footprint” without adding clear, unique value. These doorway campaigns manifest themselves as pages on a site, as a number of domains, or a combination thereof. To improve the quality of search results for our users, we’ll soon launch a ranking adjustment to better address these types of pages. Sites with large and well-established doorway campaigns might see a broad impact from this change.” Google 2015
Google will select the best title it wants for your search snippet – and it will take that information from multiple sources, NOT just your page title element. A small title is often appended with more information about the domain. Sometimes, if Google is confident in the BRAND name, it will replace it with that (often adding it to the beginning of your title with a colon, or sometimes appending the end of your snippet title with the actual domain address the page belongs to).

QUOTE: “The amount of expertise, authoritativeness, and trustworthiness (E­A­T) that a webpage/website has is very important. MC quality and amount, website information, and website reputation all inform the E­A­T of a website. Think about the topic of the page. What kind of expertise is required for the page to achieve its purpose well? The standard for expertise depends on the topic of the page.” Google Search Quality Evaluator Guidelines 2017

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.