Speed is a design decision

When a website is slow, the first instinct is to blame the hosting. Sometimes that is fair. More often, the site was designed to be slow: a large video here, a few extra fonts there, a chat widget, three tracking scripts and an image carousel nobody uses. Each decision seemed small. Together they make every visit feel sluggish.

Why speed matters to people#

The Doherty threshold describes how people stay engaged when a system responds quickly, roughly within 400 milliseconds, and how their attention starts to drift when they have to wait. Every pause is a small invitation to switch tabs, check a message or give up. A fast site keeps people in the flow of what they came to do.

What Google measures#

Google’s Core Web Vitals are a useful, public way to judge how fast a page feels. Its guidance for a good experience is:

• Largest Contentful Paint within 2.5 seconds: the main content appears quickly.
• Interaction to Next Paint within 200 milliseconds: the page responds promptly when people tap or click.
• Cumulative Layout Shift below 0.1: things don’t jump around while the page loads.

You can check any page for free with Google’s PageSpeed Insights.

Design choices that slow sites down#

• Large hero videos and images that load before anything else can appear.
• Many fonts and weights, each one a separate download.
• Third-party scripts such as chat widgets, pop-ups and trackers, which often do more work than the page itself.
• Carousels and heavy animations that load content people rarely see.
• Images that aren’t resized for phones, so a small screen downloads a huge picture.

Set a budget before you design#

A performance budget is a simple limit the whole team agrees to before design starts. It turns speed from an afterthought into a design constraint, like brand colors or page width.

When someone wants to add a new widget, the budget turns “can we?” into a clearer question: “what do we remove to make room?”

Make waiting feel shorter#

Some waits can’t be avoided, but how they feel can be improved.

• Respond instantly to every tap, even if the result takes a moment: press states, a changed label, a small spinner.
• Show structure first, with gray placeholders where content is about to appear, so the page feels as if it is already arriving.
• Show progress for anything longer than a couple of seconds, such as uploads or payments.

A quick checklist#

• Run your key pages through PageSpeed Insights, on mobile.
• List every third-party script, and remove any you can’t justify.
• Resize and compress images, and use modern formats.
• Limit fonts to the weights you really use.
• Agree a performance budget for the next redesign.

Speed rarely comes from one big fix. It comes from many small decisions made with speed in mind, which is exactly what design is.