UX Design: Complete Definition and Guide

What is UX Design?

UX Design, or User Experience Design, encompasses all the user-centred design processes aimed at ensuring a digital product meets its users' expectations. It is not merely about the visual appearance of an interface but rather about the entire experience a user has when interacting with a website, mobile application or software. UX Design covers user research, information architecture, prototyping, user testing and continuous iteration.

The term was popularised by Don Norman in the 1990s while he was working at Apple. Since then, the discipline has evolved to become an indispensable pillar of every digital project. At KERN-IT, within the KERNWEB division, UX Design is integrated from the scoping phase of every project, whether it is a showcase site built on Wagtail CMS or a bespoke business application.

Why UX Design matters

Good UX Design has a direct, measurable impact on the performance of a digital product. Companies that invest in user experience see significant increases in customer satisfaction, retention and conversion rates.

• Lower bounce rates: a smooth, intuitive user journey encourages visitors to stay on the site and explore more pages. This also improves internal linking signals and SEO performance.
• Higher conversions: every friction point eliminated from the user journey translates into a higher conversion rate. A simplified contact form, a shorter purchase funnel or clear navigation generate more leads and sales.
• Reduced support costs: when a product is intuitive, users need less help from customer support. This lowers operational costs over the long term.
• Competitive advantage: in a saturated market, user experience is often the differentiating factor. Two products with similar feature sets will be set apart by the quality of their UX.
• Accessibility and inclusivity: well-thought-out UX Design integrates web accessibility principles (WCAG), opening the product to a wider audience, including people with disabilities.

How it works

The UX Design process generally follows an iterative approach made up of several complementary phases. At KERN-IT, we apply a methodology inspired by Design Thinking, adapted to the specific constraints of each project.

The first step is user research. It involves understanding the needs, motivations and frustrations of target users through interviews, questionnaires, analysis of existing data and direct observation. This phase produces personas and user journeys that guide the entire design process.

Next comes information architecture, where content is organised and structured in a logical, intuitive way. Page hierarchy, navigation systems and interaction flows are defined. Sitemaps and tree structures are produced at this stage.

Prototyping is where ideas become tangible. Low-fidelity wireframes are created first, then interactive prototypes that simulate the final product's behaviour. At KERN-IT, we use Figma as our primary prototyping tool, enabling real-time collaboration with our clients.

Finally, user testing validates design hypotheses by observing real users interacting with the prototype. Results feed new iterations until an optimal experience is achieved.

Concrete example

Consider a project the KERNWEB team at KERN-IT might carry out: redesigning the website of a Brussels-based real-estate company (proptech). The goal is to improve the online appointment booking rate, which is stuck at 2 %.

User research reveals that visitors find the navigation confusing, the contact form asks for too much information, and property pages lack quality visuals. Based on these findings, the UX team restructures the site's architecture, reduces the form to three essential fields and implements an immersive photo gallery.

The prototype is designed in Figma, tested with a panel of five representative users and iterated twice before sign-off. The site is then developed on Wagtail CMS with TailwindCSS for the front-end, ensuring clean, performant and maintainable code. After launch, the appointment booking rate rises to 7 %, a 250 % increase.

Implementation steps

1. Define objectives: clarify business goals and success indicators (KPIs) before starting design work. For example: increase the conversion rate from 3 % to 6 % within six months.
2. Conduct user research: organise interviews, analyse existing analytics data and create personas. A minimum of five interviews is needed to surface actionable trends.
3. Design the information architecture: structure content into logical categories, define primary user flows and create a detailed sitemap.
4. Prototype and iterate: create low-fidelity wireframes, then high-fidelity mockups in Figma. Incorporate feedback at every iteration.
5. Test with real users: run user testing sessions with at least five participants per test cycle. Document friction points and improvement opportunities.
6. Develop and measure: translate validated designs into front-end code (TailwindCSS) integrated with the CMS (Wagtail). Measure results with analytics tools and iterate continuously.

Related technologies and tools

• Figma: the collaborative design tool used by KERN-IT for wireframing, prototyping and building design systems.
• Wagtail CMS: the Django-based CMS used by KERN-IT, offering an intuitive admin interface that enhances the content editor experience.
• Tailwind CSS: a utility-first CSS framework used to implement designed interfaces, ensuring consistency and development speed.
• Google Analytics / Hotjar: behavioural analytics tools for measuring the impact of UX decisions on key metrics.
• Lighthouse: a Google tool built into Chrome for auditing a website's performance, accessibility and best practices.

Conclusion

UX Design is not a luxury reserved for large corporations; it is a strategic investment that determines the success of any digital product. By placing users at the centre of the design process, businesses reduce the risk of failure, improve customer satisfaction and maximise return on investment. At KERN-IT, the KERNWEB division integrates UX Design at every stage of its web projects, from initial scoping to production deployment, to deliver high-performing and sustainable digital experiences.