Why “Best Practices” Don’t Exist in CRO (And What to Do Instead) (2/2)

Why persuasion in design matters

Design doesn’t sell on looks. It sells on meaning. Every word, visual, and interaction influences how users think, feel, and act.

Part one of this series covered the foundations: clarity, structure, and usability. Now it’s time to look at what actually drives action – persuasive design and copy.

The goal isn’t to trick users into clicking. It’s to make decisions easy, obvious, and credible.

Let’s go through the key good practices that help high-performing websites – including New Zealand’s top digital brands – persuade more effectively.

1. Use visual hierarchy to guide the eye

Users don’t “read” websites – they scan them. Strong visual hierarchy helps control where they look first and what they do next.

Visual hierarchy isn’t about colour trends; it’s about prioritisation. Elements that support your primary business goal (like CTAs, product benefits, and pricing) should stand out clearly.

Good practice:

• Decide on one most wanted action per page and make it the visual focal point.

• Use contrast, size, and spacing to highlight importance – not just colour.

• Rank content visually based on business goals, not internal politics.

When you get this right, your layout naturally leads users through a persuasive sequence – from attraction to understanding to action.

2. Make your typography work for comprehension

Typography is persuasion in disguise. Readability influences trust, engagement, and even conversion.

In one study, increasing body font size from 10pt to 13pt (and improving line spacing) lifted form conversions by 133%.

Good practice:

• Use 16px minimum for body copy and adjust based on your font family.

• Avoid non-traditional fonts for body text – they slow reading and reduce comprehension.

• Keep line length between 50–75 characters for optimal readability.

• Break content with subheadings every 1–2 paragraphs; structure improves scanning.

Readable content keeps people engaged long enough for persuasion to work.

3. Simplify your web forms – but not too much

Forms are where visitors become leads or customers. That’s where friction shows up.

Reducing form fields from 11 to 4 can increase submissions by 160% and conversions by 120%, without hurting lead quality. But shorter isn’t always better. In some cases, longer forms improve perceived credibility and lead quality.

Good practice:

• Remove unnecessary fields, but test each change.

• Use multi-step forms for long processes – they can lift conversions by 20%+.

• Place easy fields (name, email) first to create momentum.

• Align labels above form fields for easier scanning.

If your form feels conversational and transparent, users will trust it.

4. Speed is persuasion

Speed is invisible persuasion. Users associate speed with competence and credibility.

47% of users won’t wait more than two seconds for a page to load. That’s not impatience – that’s behavioural bias. A delay feels like a lack of care.

Good practice:

• Keep server response time under 200ms.

• Use caching and CDNs to reduce load time across NZ and international audiences.

• Compress and combine files; aim for under 30 requests per page.

• Regularly track load time in GA4 using custom reports.

A one-second delay can cost thousands in lost conversions – and it’s easily preventable.

6. Treat internal search as a conversion tool

Search users are high-intent visitors. They know what they want and don’t want to browse.

Making your search bar visible and smart can multiply conversions. Many tests have shown an increase in sales by simply making a search bar sticky at the top on mobile.

Good practice:

• Make your search box large and central – not buried in a header.

• Enable auto-suggest and product images in search results.

• Track search queries to understand demand and missed opportunities.

Internal search isn’t just usability – it’s a direct window into buying intent.

7. Persuade through relevance, not redesigns

Many brands jump into radical redesigns expecting instant results. Most of the time, they destroy what was already working.

Evolutionary design – small, hypothesis-driven iterations – consistently outperforms major redesigns because it preserves proven performance patterns .

Good practice:

• Test incremental changes to layout, copy, or structure.

• Keep what already works; improve what blocks conversions.

• Benchmark before and after every change.

Good persuasion builds over time. Redesigns reset trust.

8. Don’t overlook phone leads

In some industries, the most persuasive call to action isn’t a button – it’s a phone number.

Phone leads convert better because they’re intentional and immediate.

Good practice:

• Make phone numbers prominent – above the fold and again ~75% down the page.

• Add a benefit statement next to the number (“Call now for free assessment”).

• Use call tracking and Google Analytics events to measure impact.

For NZ businesses in service-based industries, optimising phone calls can outperform any form or checkout improvement.

9. Copy that persuades comes from user insight

Effective copy isn’t clever – it’s grounded in how people think. Start with user research, not adjectives.

Good practice:

• Lead with clarity: what is it, who is it for, why it matters.

• Mirror user language – use the exact phrases customers use in interviews and search.

• Focus on benefits tied to outcomes, not product features.

When your message sounds like it came from your audience, persuasion happens naturally.

More CRO tips to come...

This series only scratches the surface of what drives high-performing websites. We’ll continue exploring how to scale CRO capability across organisations – connecting testing, analytics, and design into one performance-driven system.