The SEO practices to avoid fall into two groups: tactics Google's spam policies name (keyword stuffing, buying links, scaled content, cloaking, hidden text, doorway pages) and honest mistakes that waste effort, such as ignoring search intent, chasing head terms, and treating SEO as a one-off. The first group can erase rankings; the second guarantees they never arrive.
This usually comes up after a traffic drop you cannot explain, or when an agency proposal lists tactics you half-recognise as risky. Here is the full list, roughly ordered by how much damage each one does, with Google's own policy wording where it exists.
The practices Google punishes
Google's spam policies name each of the practices below, and a site that uses them can be demoted or removed from results.
Keyword stuffing. Google defines it as "the practice of filling a web page with keywords or numbers in an attempt to manipulate rankings in Google Search results." Repeating the target phrase in the copy, the headings, the alt text and the footer reads as exactly that. Modern Google understands synonyms and topics; a page can rank for "backlink exchange" without saying it fourteen times. Write for a reader, mention the topic naturally, and stop.
Buying cheap bulk links. The $30-for-500-backlinks packages are the fastest way to hand your site a spam profile. Google's link spam policy lists "Buying or selling links for ranking purposes", including "Exchanging money for links, or posts that contain links" and "Exchanging goods or services for links". The networks selling these packages are the ones Google has already mapped, so outcomes range from ignored to penalised. If you are tempted by paid links at all, read is it worth paying for backlinks first, and know that what makes a backlink toxic applies to links you acquire, not just links that happen to you.
Mass-produced thin content. Publishing hundreds of near-identical or machine-generated pages with no added value is what Google's scaled content abuse policy exists for. Google announced that policy on 5 March 2024 alongside its March core update, and said it expected the combination of that update and earlier work to "reduce low-quality, unoriginal content in search results by 40%" (Google's announcement). The same post added expired domain abuse and site reputation abuse (in force from 5 May 2024) to the spam policies. The test is not "was AI involved?" but "does this page tell a searcher something a hundred other pages don't?" If not, don't publish it.
Cloaking and hidden text. Showing Google different content than users see, white text on white backgrounds, tiny hidden keyword blocks. This is 2005-era spam that still gets attempted and still gets caught; both "Cloaking" and "Hidden text and link abuse" are named policies. Worth reading what cloaking is and how to check your own site even if you would never do it deliberately, because hacked sites cloak without their owner noticing.
Doorway pages. Dozens of near-identical "[service] in [city]" pages whose only job is to funnel visitors to one central page. Google lists this as "Doorway abuse". Most people who build these think they are doing local SEO; what are doorway pages covers the test that separates a legitimate location page from a doorway.
Over-optimised anchor text. If every link pointing at your page says your exact target keyword, you have built a pattern no natural link profile has. Vary anchors (branded, partial, generic), especially in links you control, like exchanges. This one deserves its own deep-dive: what to avoid when building backlinks.
Aggressive link schemes. Google's policy wording is "Excessive link exchanges ("Link to me and I'll link to you") or partner pages exclusively for the sake of cross-linking", alongside private blog networks and automated link drops in comments and forums. Note the word excessive: a modest number of relevant, in-content reciprocal links is normal web behaviour. The line is scale, relevance and intent, and how many link exchanges is safe covers where that line sits.
The mistakes that just waste your year
None of these will get you penalised, but each one quietly caps what the rest of your work can achieve.
Ignoring search intent. Ranking a product page for a research query (or a blog post for a buying query) means either no ranking or no conversions. Before writing, search the keyword and look at what is already ranking: that is Google telling you what searchers want for that query. Match the format or pick a different keyword.
Chasing volume over winnability. New sites burning months on head terms like "SEO" or "insurance" are competing against decade-old authorities. The winnable ground is specific long-tail queries, with less volume each, but they add up and they actually rank.
Neglecting titles and meta descriptions. Still the most common basic miss: pages with duplicate titles, missing descriptions, or titles that don't contain the topic at all. It is an hour of work per batch of pages and it directly affects both ranking and click-through.
Treating SEO as one-and-done. SEO is compounding maintenance, not a launch task. Content ages, competitors publish, algorithms shift. Sites that win revisit and update; sites that "did SEO in 2023" decay.
Building zero links. Not a penalty, just a ceiling. Content without authority stalls on page two behind competitors with ordinary content and real backlink profiles. The white-hat routes are earned links, guest posts and relevant one-for-one exchanges. We make Backlinkster for the last of those: it pairs you with relevant real sites for in-content swaps, and each swap is verified by API. It is not the right fit if you can't publish articles on your own domain, or if you want dozens of links a month from one source, which starts to look like the excessive pattern above.
Skipping measurement. No Search Console means no idea what is indexed, what is ranking, or what broke. You can't fix what you can't see, and it is free.
The one-question filter
Nearly everything on the avoid-list fails the same test: "Would I do this if Google didn't exist?" Stuffing keywords, hiding text, buying spam links, generating a thousand empty pages: nobody does these for human readers. They are performed at the algorithm, and the algorithm is specifically built to detect things performed at it. Writing useful pages, earning and trading links with relevant real sites, keeping your site fast and organised: those make sense even with no search engine watching, which is exactly why they keep working through every update.
Avoid the tactics aimed at the machine, do the work aimed at people, and measure as you go. That is the whole discipline. The rest is detail, and the golden rule of SEO is the same idea from the other direction.
Frequently asked questions
What SEO practices should you avoid? Avoid anything Google's spam policies name: keyword stuffing, buying or selling links, scaled low-value content, cloaking, hidden text, doorway pages and excessive link exchanges. Then avoid the quiet mistakes: ignoring search intent, chasing head terms, duplicate titles, never updating pages, and building no links at all.
Is buying backlinks against Google's rules? Yes. Google's link spam policy lists "Buying or selling links for ranking purposes", including paying for posts that contain links or trading goods and services for them. Paid placements are only acceptable when marked with rel="sponsored" or rel="nofollow", which means they pass no ranking value.
Does keyword stuffing still hurt rankings? Yes. Google still lists keyword stuffing as a spam policy, defined as filling a page with keywords or numbers to manipulate rankings. Modern systems understand synonyms, so repeating a phrase adds nothing and can trigger a demotion.
Does Google penalise AI-generated content? Not for being AI-generated. Google's scaled content abuse policy targets content produced at scale to boost rankings regardless of how it was made, whether by automation, by people, or both. One useful page written with AI help is fine; five hundred thin variations are not. See does Google penalise AI-generated content.
Are link exchanges a bad SEO practice? Only when excessive. Google's policy wording targets "Excessive link exchanges" and partner pages that exist only for cross-linking. A small number of relevant, in-content reciprocal links between real sites is ordinary web behaviour. Keep the scale modest and the relevance high.
Related: What is keyword cannibalization? · Does Google penalize AI-generated content? · What is a canonical tag in SEO? · What to avoid when building backlinks · What is a bad backlink? · Link swaps without a Google penalty · What is scaled content abuse? · What is cloaking in SEO? · What are doorway pages?