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Nik Dyankov
Nik Dyankov

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Sites speed optimisation is a destination, not a journey

Imagine walking into a grocery store. The doors stick as you try to open them, the aisles are cluttered, and the checkout line moves at a glacial pace. How likely are you to return? A slow website feels just as frustrating. Performance, like customer service in a store, defines the experience people have with your business.

Yet, for many organisations, performance is treated as a box to tick or a single metric to hit. Tools like Lighthouse scores are celebrated in isolation, with little understanding of what they represent or the customers they impact. The reality is that performance isn’t just a technical achievement; it’s an ongoing commitment - a destination that evolves with your customers, your business, and the web itself.

Let’s explore what performance truly means and how to approach it in a way that serves your most valuable asset: your customers.

Performance beyond metrics

Far too often, performance is mistaken for search engine optimisation (SEO). While speed does influence Google rankings, that’s not where its value lies. Performance is about delivering a seamless, delightful experience to your users where every second counts!

Google Data, Global, n=3,700 aggregated, anonymised Google Analytics data from a sample of mWeb sites opted into sharing benchmark data, March 2016.

Performance isn’t a “tech thing”. When we shift the focus from algorithms to people, the importance of performance becomes clear. Customers expect your site to load quickly and function smoothly. Customers don’t see your site through the lens of Lighthouse scores, they simply feel the frustration, or satisfaction of interacting with your site.

This is why performance must be a priority at every level, especially senior leadership. It’s not about appeasing developers or passing tests - it’s about delivering the best possible experience to customers and building long-term loyalty.

Tools are just the start

When it comes to measuring performance, there’s no shortage of tools. But understanding their strengths and limitations is critical.

Take Google PageSpeed Insights, for example. It provides excellent real-world data by incorporating field metrics (per page and per origin) like Core Web Vitals. These metrics, Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS), reflect how users actually experience your site.

Lighthouse, another popular tool, is useful for snapshots but can be misleading. A Lighthouse score is highly variable, influenced by factors like network conditions and device settings. It’s a great starting point but not a reliable indicator of ongoing performance as it is a snapshot of site's performance in moment of time.

For deeper insights, WebPageTest is invaluable. It offers detailed waterfall charts, which show how individual elements load, and allows you to simulate different conditions or block third-party scripts. This flexibility helps isolate bottlenecks, making it a more actionable tool than Lighthouse for diagnosing and resolving issues.

Two ways to look at your site

Example of Dareboost dashboard

One of the most effective ways I’ve found to analyse areas of improvement when it comes to performance optimisation is by examining your site through two lenses:

  1. AS-IS performance: This includes everything on your site: third-party scripts, tracking pixels, and ads. It provides a real-world view of what users are experiencing.

  2. 3RD-PARTY-FREE Performance: By stripping away external dependencies, you can see how much of the load is coming from your own code base versus third-party scripts. This perspective helps you attribute bottlenecks and decide where to focus your efforts.

For example, you might discover that a third-party ads script is responsible for 40% of your page load time. With this knowledge, you can decide whether the revenue it generates justifies the performance cost—or if it’s time to explore alternatives.

Context matters

When evaluating performance, it’s crucial to consider the domain and purpose of the site. Not all scores are created equal, and a number on its own doesn’t tell the full story.

Take, for example, a statically generated blog. These sites are often lean and simple by design, with fewer dynamic elements. It’s not uncommon for them to achieve Lighthouse scores in the high 80s or 90s. That’s fantastic, but it’s also expected. The nature of their content and architecture lends itself to speed.

Now compare that to an e-commerce site with a Lighthouse score of 75. At first glance, it might seem like the blog is “better.” But in reality, that e-commerce site might be performing exceptionally well, given its complexity and 3rd parties. Unlike the blog, it has to handle dynamic product catalogs, personalised recommendations, inventory tracking, and secure transactions, all while delivering a smooth experience for customers.

The point is, performance scores should never be viewed in isolation. They need to be interpreted in the context of the site’s purpose, functionality, and user expectations. A blog and an e-commerce site serve entirely different needs, and their performance metrics should reflect that.

For e-commerce, a score of 75 with smooth page transitions, a fast checkout process, and minimal layout shifts might be far more impactful to the business than a static blog with a score of 85. Understanding this nuance helps prioritise improvements that matter most for your specific domain and audience.

Refactoring when and as needed as a business investment in the future site performance

Performance optimisation isn’t a one-time task, it’s an investment in your site’s future. Just as a growing company re-tools its processes to handle increased demand, a growing site must simplify and restructure its codebase to remain scalable.

Consider it like renovating a house. When the foundation is strong and the layout is efficient, every upgrade you make adds value. But if the house is cluttered with quick fixes and outdated materials, every improvement becomes a chore.

The same principle applies to code. Clean, semantic code is easier to maintain and optimise. As your site grows more complex, taking the time to refactor and simplify ensures that you’re building on solid ground.

Real data equals to real impact

One of the most powerful shifts you can make is prioritising real user monitoring (RUM). While synthetic tests like Lighthouse and WebPageTest are helpful, they don’t capture the nuances of real-world usage. Tools like SpeedCurve RUM or PageSpeed Insights can show how actual users experience your site across devices, locations, and connection speeds.

This combination of quantitative and qualitative data is essential. RUM tells you what’s happening, while tools like WebPageTest help you understand why. Together, they provide a complete picture, guiding your optimisation efforts with precision.

The Future of performance optimisation is in simplification

As the web becomes more complex, the best approach to optimise site's performance is one of simplicity. Evaluate over-complicated business logic, strip away unnecessary complexity. Focus on delivering the essentials quickly and beautifully. Only because a site's codebase is hard to maintain with lots of knowledge concentrated in a few developers doesn't mean it provides more value to your customers. In fact most of the time is exactly the opposite. Align your goals with customer expectations and measure success in terms of satisfaction and loyalty, not just scores.

At its core, performance isn’t about passing a test or hitting a number. It’s about creating an experience that reflects your brand’s values and respects your customers’ time. By treating performance as a destination rather than a journey, you’ll not only meet today’s challenges but also prepare for the opportunities ahead.


What’s your biggest performance challenge? Let’s discuss in the comments! Feel free to let me know which brand I should evaluate in terms of performance and I will generate complementary site speed report for it!

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