I recently opened up the theme running one of my websites. Not the settings screen. The actual code. I have 33 years in technology, so this was not my first look under a hood, but I was still surprised by what I found.
The site had been slow for a while, and I had eliminated everything else. Hosting fine, plugins lean, caching aggressive, images optimized. The only suspect left was the theme. So I unzipped it and started reading.
What I found was not a theme. It was a collection of parts.
This matters beyond speed. As I laid out in the opening article of this series, your website is your beacon on the internet. For a service business it is where your credibility lives, and everything attached to it, starting with the theme, either strengthens that beacon or quietly degrades it.
The monster on the slab
There was JavaScript running an animation loop for a cursor follower, a decorative dot that trails your mouse around the screen. Trendy effect a few years back. Here is the thing: no page on my site ever displayed that element. The template that would have rendered it was never called from anywhere. But the code still ran on every single page load, attaching mouse listeners to every button, link, and form field, updating the position of an element that did not exist. Every visitor’s browser did that work for nothing.
There was CSS for a media player the theme never used. There were three different generations of settings systems living side by side, each added when the developers needed something the previous one could not do, none removed when its replacement arrived. There were hooks for features that had been taken out, still firing on every request, calling functions that did nothing.
None of this was broken, exactly. The site worked. It just carried the dead weight on every page, for every visitor, forever.
I call it a Frankenstein’s monster because that is what it is. Nobody sat down and designed this theme. Somebody assembled it, from pieces built at different times, by different people, for different purposes, and stitched the seams just well enough that it would stand up and walk.
How the monster gets built
Once you understand how commercial themes are made, the mess stops being surprising and starts being inevitable.
Theme shops do not build themes from scratch. They build a base once, a big one, loaded with every module a customer might ever want: mega menus, sliders, tickers, demo importers, cursor followers, a dozen header layouts. Then they produce new themes by reskinning that base. Change the fonts, change the colors, swap the demo content, give it a new name, publish it as a separate listing.
The economics drive everything. A theme shop makes money per listing. Building from scratch produces one listing per year of work. Reskinning produces a listing per week. Guess which approach wins.
The theme on my site was exactly this: a reskin of another theme by the same vendor, which was itself assembled from modules that appear across the vendor’s whole catalog. My theme was a diff on top of a pile of diffs.
And here is the part that explains the dead code. When your product is an assembly of shared modules, removing anything is expensive. Strip the cursor follower out of one theme and you have created a special case your build process must track forever. Leave it in and it costs you nothing. It only costs your customers, a little, on every page load, multiplied by every visitor, multiplied by every site running the theme. That cost is invisible to the vendor, so the vendor never pays it.
A fact worth knowing: being in the official WordPress theme directory means less than most people assume. Themes go through a largely automated check plus a volunteer review focused on requirements compliance, not code quality. Passing that gate means the theme follows the rules. It does not mean anyone vouched for the engineering. My Frankenstein came from the official directory.
Why your caching plugin cannot save you
The standard advice when a WordPress site is slow is to add a caching plugin, and caching does help. It helps the way painkillers help a broken leg.
Caching stores the finished page so the server does not rebuild it for each visitor. That fixes server time. It does nothing about what is in the page. If your theme ships 300 kilobytes of styles for modules you do not use, the cache serves those 300 kilobytes faster. If the theme runs an animation loop for an element that does not exist, that loop runs in your visitor’s browser, after the cache has done its job, on every page view. No cache layer touches it.
This is why so many site owners end up in a loop I have watched for years: the site is slow, they add an optimization plugin, the score improves a little, the site is still slow, they add another plugin, and now they have two more moving parts and the same underlying problem. The weight is in the theme, and the theme is the one thing the optimization tooling works around instead of on.
So what do you actually do?
Nobody is going to write their own theme, and I am not going to pretend otherwise. The honest answer depends on where you are.
If you are choosing a theme, choose by what is missing. The marketing pushes you the other way. Theme listings compete on feature count: 50 demos, 12 sliders, unlimited headers. Every one of those features is code that ships to your visitors whether you use it or not. A theme that does less is not a lesser theme. It is a smaller monster. Find a theme that does what you want rather than a box with tons of parts in it. The default themes that come with WordPress are among the few actually designed from scratch, by people whose incentive is quality rather than listings, and the newer block themes are structurally leaner than the old assemble-everything generation. They are not glamorous. They are also not carrying three settings systems and a ghost cursor.
Test before you commit. Every theme has a live demo, and the demo is the theme on its best behavior, running the vendor’s own content on the vendor’s own hosting. Run that demo through PageSpeed Insights before you install anything. Two minutes. If the demo scores poorly, your site will score worse, because your site adds your plugins and your content on top. A slow demo is the vendor telling you, in writing, that they do not care. Believe them.
If you are already married to a monster, contain it. You cannot easily strip a bad theme, but you can stop feeding it. Every theme option you enable, every demo section you import, every bundled plugin you activate adds weight. Turn off what you do not use, keep the plugin count ruthless, and let good caching mask what remains. Containment is not a cure, but it is real relief, and for a hobby site it is enough.
If your site earns money, fork it once and own it. This is what I finally did. I had the theme copied into a private version and stripped of everything my site does not use: the phantom cursor, the unused player, the dead hooks, the styles for absent modules. One-time job, and the difference was not subtle. The site went from sluggish to scoring 100 on desktop performance. More important, I now know what every line in that theme does, because every line that did nothing is gone. This is the kind of work I take on for clients whose sites have earned it.
The moral of the monster
The lesson is not that theme developers are villains. They respond rationally to a marketplace that rewards listings and feature lists and never audits what ships inside. The lesson is that the incentives guarantee Frankenstein’s monsters, so stop being surprised when you get one.
Assembled is not the same as designed. Something built by stitching together parts that were never meant to meet will stand up and walk, and it will even pass for the real thing at a distance. But open it up and you will find the seams, the scars, and a cursor chasing a mouse across a screen it never appears on.
Next in this series: what happened when I tried to leave two page builders, one because it was bad and one because it was excellent. The exit cost more than either arrival, and that asymmetry is the subject of Divorcing Your Page Builder.
The Guides That Get Your Book Written, Published, and Sold
Four short, practical guides on writing, publishing, and selling your book, plus the occasional note when there's something worth your time. No fluff, no daily inbox clutter. Drop your email and they're yours.
We use MailerLite to manage our list and send these emails. Your address is used only to send you what you signed up for. We will not sell it, share it, or use it for anything else, and you can unsubscribe anytime.