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Performance

Why a slow website is a leaky bucket

6 min read · Written by the Kavana studio

Website performance speedometer

You can pour money into ads and content, but if your website is slow, you're filling a bucket with a hole in the bottom. Speed isn't a technical nicety — it's a business metric that touches conversions, rankings and brand perception all at once.

What slowness actually costs

Study after study finds the same pattern: as load time climbs, conversions fall. A site that takes five seconds to become usable loses a meaningful share of visitors before they ever see your offer. On mobile connections, the effect is sharper still.

The metrics worth watching

  • Largest Contentful Paint — how quickly the main content appears.
  • Interaction to Next Paint — how responsive the page feels when tapped.
  • Cumulative Layout Shift — how much the page jumps around while loading.

These three form the core of Google's Web Vitals, and they map neatly onto how a real person experiences your site: does it appear fast, respond fast, and stay put?

Where the weight usually hides

In our audits, the biggest offenders are almost always the same: oversized images shipped at full resolution, bloated third-party scripts, and heavy page builders that load far more code than the page needs. The fixes are rarely glamorous, but they're effective.

A sensible order of attack

  • Compress and correctly size every image — this alone often halves page weight.
  • Audit third-party scripts and remove anything that doesn't earn its place.
  • Defer non-critical JavaScript so content appears sooner.
  • Cache aggressively and serve assets from close to your visitors.

How fast is fast enough?

Aim to have your main content visible in under two and a half seconds on a mid-range phone, and interactions responding almost instantly. Beyond a certain point, chasing milliseconds has diminishing returns — but most sites are nowhere near that point yet.

The takeaway

Fixing speed rarely requires a rebuild. It requires discipline: measure honestly, tackle the heaviest offenders first, and keep an eye on the numbers over time. Plug the hole, and everything else you pour in starts to count.

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