Common Technical SEO Mistakes That Hurt Your Marketing

Effective technical SEO is the bedrock of any successful online marketing strategy. Without it, even the most brilliant content can struggle to rank. Technical SEO focuses on optimising your website’s infrastructure to ensure search engines can easily crawl, index, and understand your content. Neglecting these vital aspects can lead to lost traffic, reduced visibility, and ultimately, lower conversions. Are you making common technical SEO mistakes that are silently sabotaging your website’s performance?

Ignoring Mobile-First Indexing

In 2026, it’s no longer a question of whether your site is mobile-friendly; it’s a question of whether it’s mobile-first. Google primarily uses the mobile version of a website for indexing and ranking. This means your website’s mobile experience directly impacts your search engine performance. A poor mobile experience will negatively impact your rankings.

Here are some common mobile-first indexing mistakes to avoid:

1. Missing or incomplete content: Ensure all essential content, including text, images, and videos, is present on the mobile version of your site. Avoid hiding content behind tabs or accordions unless absolutely necessary, as Google may not fully index it.
2. Slow mobile page speed: Mobile users expect fast loading times. Optimise images, leverage browser caching, and minify code to improve mobile page speed. Use tools like PageSpeed Insights to identify and fix speed bottlenecks.
3. Mobile usability issues: Ensure your site is easy to navigate on mobile devices. Avoid using small fonts, tiny tap targets, and intrusive interstitials. Use a responsive design that adapts seamlessly to different screen sizes.

According to data from Statista, mobile devices (excluding tablets) generated 54.8% of global website traffic in the first quarter of 2024.

Neglecting Core Web Vitals

Core Web Vitals are a set of specific factors that Google considers important in a webpage’s overall user experience. They measure aspects of web usability such as load time, interactivity, and the stability of content as it loads. Ignoring these metrics can significantly hurt your rankings.

The three Core Web Vitals are:

• Largest Contentful Paint (LCP): Measures the time it takes for the largest visible content element on the page to become visible. Aim for an LCP of 2.5 seconds or less.
• First Input Delay (FID): Measures the time it takes for a browser to respond to a user’s first interaction with a page (e.g., clicking a link or button). Aim for an FID of 100 milliseconds or less.
• Cumulative Layout Shift (CLS): Measures the visual stability of a page. It quantifies how much unexpected layout shifting occurs during page load. Aim for a CLS score of 0.1 or less.

To improve your Core Web Vitals, consider the following:

• Optimise images: Compress images to reduce file size without sacrificing quality. Use modern image formats like WebP.
• Minify CSS and JavaScript: Remove unnecessary characters from your code to reduce file sizes.
• Leverage browser caching: Enable browser caching to store static assets on users’ devices.
• Use a Content Delivery Network (CDN): Distribute your website’s content across multiple servers to improve loading times for users around the world.

My experience working with clients has shown that improving Core Web Vitals often leads to a noticeable increase in organic traffic within a few months.

Poor Website Architecture and Internal Linking

A well-structured website is crucial for both users and search engines. Website architecture refers to the way your website’s content is organised and linked together. A clear and logical website architecture makes it easier for search engines to crawl and index your content, and it also improves the user experience.

Here are some common website architecture mistakes to avoid:

• Flat website structure: A flat website structure has too many pages directly linked from the homepage, making it difficult for search engines to understand the hierarchy and importance of different pages.
• Orphaned pages: Orphaned pages are pages that are not linked to from any other page on your website. Search engines may have difficulty finding and indexing these pages.
• Inconsistent navigation: Inconsistent navigation can confuse users and make it difficult for them to find what they’re looking for.

Internal linking is the practice of linking from one page on your website to another. Internal links help search engines understand the relationship between different pages on your website and can also improve the flow of link equity (ranking power) throughout your site.

Best practices for internal linking include:

• Using relevant anchor text: Use descriptive and relevant anchor text when linking to other pages on your website. Avoid using generic anchor text like “click here.”
• Linking to relevant pages: Only link to pages that are relevant to the content of the page you’re linking from.
• Varying anchor text: Use a variety of anchor text when linking to the same page from different pages on your website.

A study by Ahrefs in 2023 found that websites with a well-defined internal linking structure tend to rank higher in search results.

Ignoring Structured Data Markup

Structured data markup (also known as schema markup) is code that you can add to your website to provide search engines with more information about your content. This helps search engines understand the context of your content and display it in a more informative way in search results.

Benefits of using structured data markup include:

• Enhanced search results: Structured data markup can enable rich snippets, which are enhanced search results that include additional information such as ratings, reviews, prices, and availability.
• Improved click-through rates: Rich snippets can make your search results more appealing and informative, which can lead to higher click-through rates.
• Better understanding of your content: Structured data markup helps search engines understand the context of your content, which can improve your rankings for relevant keywords.

Common types of structured data markup include:

• Article: For news articles, blog posts, and other types of articles.
• Product: For product pages on e-commerce websites.
• Recipe: For recipe pages.
• Event: For event listings.
• FAQ: For frequently asked questions pages.

You can use Google’s Rich Results Test to validate your structured data markup and ensure that it’s implemented correctly.

Not Optimising for Voice Search

Voice search is becoming increasingly popular, with many people using voice assistants like Siri, Alexa, and Google Assistant to search for information online. Optimising your website for voice search can help you reach a wider audience and improve your visibility in search results.

Here are some tips for optimising for voice search:

• Focus on long-tail keywords: Voice searches tend to be longer and more conversational than text-based searches. Focus on targeting long-tail keywords that reflect the way people speak.
• Answer questions directly: Voice search results often provide direct answers to users’ questions. Make sure your website provides clear and concise answers to common questions in your industry.
• Use natural language: Write in a natural and conversational style that is easy for voice assistants to understand.
• Optimise for local search: Many voice searches are local in nature. Make sure your website is optimised for local search by including your business name, address, and phone number (NAP) on your website and in online directories.

A 2025 report by Juniper Research projected that voice commerce transactions will reach $80 billion globally by 2026.

Ignoring Website Security (HTTPS)

Website security is not just a technical issue; it’s also a marketing issue. Google uses HTTPS as a ranking signal, and users are more likely to trust websites that are secure. If your website is not using HTTPS, you’re not only putting your users’ data at risk, but you’re also hurting your search engine rankings.

HTTPS (Hypertext Transfer Protocol Secure) is a secure version of HTTP, the protocol used for communication between web browsers and web servers. HTTPS encrypts the data transmitted between the browser and the server, protecting it from eavesdropping and tampering.

To enable HTTPS on your website, you need to obtain an SSL/TLS certificate from a Certificate Authority (CA) and install it on your web server. Most web hosting providers offer SSL/TLS certificates as part of their hosting packages.

In addition to enabling HTTPS, you should also take other steps to secure your website, such as:

• Using strong passwords: Use strong and unique passwords for all your website accounts.
• Keeping your software up to date: Regularly update your website’s software, including your content management system (CMS), plugins, and themes.
• Using a web application firewall (WAF): A WAF can help protect your website from common web attacks, such as SQL injection and cross-site scripting (XSS).

Avoiding these common technical SEO mistakes is essential for effective marketing. By prioritising mobile-friendliness, optimising Core Web Vitals, structuring your website effectively, implementing structured data, adapting to voice search, and ensuring website security, you can significantly improve your website’s visibility in search results and drive more organic traffic.

In conclusion, technical SEO, while sometimes complex, is a critical component of any successful online strategy. Take the time to audit your site, address the issues outlined above, and continuously monitor your progress. Your efforts will be rewarded with improved rankings, increased traffic, and a better user experience. Start today by running a site audit with a tool like Semrush or Ahrefs to uncover technical issues and begin improving your website’s foundation for SEO success.