Why Your Website Speed Is Killing Your Conversions

Speed is not a nice-to-have. It is a fundamental part of your website's commercial performance, and most business owners dramatically underestimate how much a slow site is costing them. Google has published research showing that a one-second delay in mobile load times reduces conversion rates by up to 20%. Amazon calculated that every 100 milliseconds of latency costs them 1% in revenue. Those are Amazon-scale numbers, but the principle applies to businesses of every size. ## Why slow sites lose customers The web has trained people to expect instant results. When a page does not load within two or three seconds, a significant proportion of visitors simply leave. They do not wait. They hit the back button and try the next result. This is especially true on mobile, where network conditions vary and patience is lower. More than half of all web traffic now comes from mobile devices, and slow mobile performance is one of the most common reasons businesses with otherwise decent websites see poor conversion rates. ## The Google factor Since 2021, Google has incorporated Core Web Vitals into its ranking algorithm. Core Web Vitals are a set of performance metrics that measure how fast your pages load, how quickly they become interactive, and how stable the layout is as content loads. A slow site does not just lose customers directly — it loses organic visibility too. Google actively demotes pages that perform poorly on these metrics, meaning your competitors with faster sites rank above you, even if your content is better. ## Common causes of slow websites In our experience, the most common culprits are: **Unoptimised images.** A homepage with eight full-resolution JPEG images that have not been compressed or resized for web will be painfully slow on mobile. This is one of the easiest fixes and often has the biggest impact. **Too many plugins.** On WordPress in particular, each active plugin adds overhead. A site with 40 plugins loading scripts and stylesheets on every page will always be slower than one with 10 well-chosen ones. **Cheap shared hosting.** As we covered in [our post on hosting costs](/insights/real-cost-of-cheap-web-hosting), budget hosting means shared resources. When the server is busy, your site is slow. **No caching.** Every time an uncached page loads, the server builds it from scratch — querying the database, assembling the HTML, and serving it to the browser. Proper caching serves a pre-built version instead, which is dramatically faster. **Render-blocking resources.** JavaScript and CSS files that load before the page content renders will delay how quickly users see anything on screen. Proper asset loading order matters significantly. ## How to find out how fast your site is Google's [PageSpeed Insights](https://pagespeed.web.dev) tool gives you a free, detailed breakdown of your site's performance on both mobile and desktop. It tells you what is slow and why. If your score is below 50 on mobile, you have a meaningful problem worth addressing. ## What a proper fix looks like A performance audit and optimisation is usually a well-defined piece of work. We typically look at: - Image optimisation and next-gen format conversion (WebP) - Caching configuration - Asset minification and load order - Database query optimisation - Hosting upgrade recommendations - Plugin audit on WordPress sites For most small business websites, a focused performance pass can take a site from a PageSpeed score in the 30s to the 80s or 90s. The impact on bounce rate and conversions is measurable. If your site feels slow and you want to understand why, [get in touch](/contact). We will take a look and tell you honestly what the problem is and what it will take to fix it.