Slow WordPress site? It's rarely a mystery. Nearly always it traces back to the same short list of causes, and most of those come from how the site was built rather than where it happens to be hosted. Here's what actually drags a WordPress site down. And the budget I hold my own builds to, so it doesn't happen in the first place.
The usual culprits
Start with the theme. A heavy off-the-shelf one loads styling for hundreds of features you will never once touch. Then the page builders, a whole stack of them, each adding its own CSS and JavaScript to every page. Uncompressed images, dropped straight into the media library at full size. Fonts pulled in from third parties, blocking the page while they fetch. And a separate plugin for every small job, each one shipping its own front-end assets whether you use them or not. Plugins everywhere.
On its own, none of these is fatal. Put them together, though, and that's why a plain brochure site takes four seconds to load on a phone. It adds up.
The budget I build to
On my builds, every page has to come in under a fixed budget, and I measure it on a mid-range phone over a throttled connection. Total compressed CSS under 75KB. First-load JavaScript under 100KB. A Google Lighthouse mobile score of 95 or better. Largest Contentful Paint under two and a half seconds. Miss any of those and the page doesn't ship until it's sorted. The number isn't negotiable, and that single constraint quietly forces good decisions everywhere else in the build.
How you actually hit it
Ship less. One stylesheet, one script, both deferred, instead of a dozen competing plugin bundles. Then strip out what WordPress loads by default that most sites never use: the emoji script, the block-library CSS, jQuery where nothing actually needs it. Self-host your fonts as woff2 so the text shows straight away instead of hanging on a web request. Serve images as WebP or AVIF at the right size, prioritise the one that matters, and load the rest lazily. And plugins? Say no by default.
None of this is exotic. It's discipline, applied on every single page, and measured rather than assumed. Measure first.
Why it's worth it
A fast site converts better, ranks better, and costs less to run, because it isn't being propped up by caching plugins fighting a bloated build underneath. Slow site, no idea why? That's usually fixable. You can see my full approach on the how I build page, or book a free 30-minute surgery and I'll tell you honestly what's dragging yours down.
Free 30-min surgery
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