Most agencies can assemble a WordPress site. Fewer want to own the bit where a page builder has been stretched past what it was designed for and nobody can maintain the result.
A stock theme and a page builder gets a site live quickly, and for a simple brochure site that is a reasonable trade. The difficulty arrives when the design has specific requirements, or the client needs to maintain it, or there are forty pages that all have to stay consistent.
At that point the builder stops saving time and starts costing it. Every page is a one-off layout, nothing is reusable, the markup is enormous, and a change to the design means editing forty pages by hand. Two years later nobody can safely touch it.
The alternative is building the design as proper editor blocks: your layouts available as components the client can place, consistent by construction, and light enough to be quick. More work up front and considerably less afterwards.
Built to your design rather than a stock theme bent towards it. The markup is yours, and it stays legible.
Your layouts as components the client places themselves, so the design holds as content is added.
Content types and fields arranged so editors can work without a developer. This is where most CMS projects are won or lost.
Custom plugins where nothing suitable exists, and an honest assessment of the ones already installed.
Caching, images and a restrained plugin stack. A clean build is quick without needing rescuing afterwards.
Several sites on one platform where that genuinely helps, rather than as a reflex.
The scale you set, not approximated. If a typeface cannot be licensed for web we tell you before the build rather than substituting it.
A layout that breaks at 900px, an interaction that will be painful on a phone. You hear about it while it is still cheap to change.
Designs rarely cover every width. Rather than invent the in-between states we agree them with you.
So your client can update content without the design falling apart, which is what protects your work after handover.
No credit in the footer, nothing in the code, nothing in the documentation. Your client sees your agency.
A five-page brochure site that will not change does not need a custom theme. We will say so rather than take the larger project.
Not the platform. A site carrying thirty plugins has thirty independent update schedules, and reducing that is often the most valuable work.
Most complaints about a CMS being awkward trace back to content modelling, not the software.
Some effects cost ten times what they look like they should. We will tell you the price rather than absorb it or drop it silently.
Contrast below AA, or an interaction that cannot be used by keyboard. We will say so, and propose an alternative that keeps the intent.
We will tell you what it would take to build properly, where a simpler approach would serve, and what the client will be able to maintain afterwards.