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concept#Product#Software Engineering#Architecture#Delivery

User Interface (UI)

The user interface (UI) denotes the visible, interactive layer through which people interact with digital systems. It covers layout, interaction and visual design to support user tasks and goals.

The user interface (UI) is the visible and interactive layer through which people interact with systems.
Established
Medium

Classification

  • Medium
  • Business
  • Design
  • Intermediate

Technical context

Frontend frameworks (e.g. React, Angular)Design systems (e.g. Material, custom component library)Analytics and A/B testing tools

Principles & goals

User-centred: decisions based on observed user needs.Clarity over style: functional communication takes precedence.Accessibility as a baseline requirement, not optional.
Build
Enterprise, Domain, Team

Use cases & scenarios

Compromises

  • Lack of user research leads to false assumptions.
  • Ignoring accessibility can have legal and reputational consequences.
  • Overly complex interfaces reduce performance and acceptance.
  • Test early and often with users.
  • Use design systems for consistency.
  • Integrate accessibility from the start.

I/O & resources

  • User research and personas
  • Business requirements and KPIs
  • Technical constraints (APIs, platforms)
  • Wireframes and interactive prototypes
  • Design system components and specifications
  • Evaluation reports and metrics

Description

The user interface (UI) is the visible and interactive layer through which people interact with systems. It includes layout, interaction patterns, information architecture and visual design. Good UI design improves learnability, efficiency and satisfaction and requires trade-offs between usability, accessibility and technical feasibility. It integrates research, prototyping and user feedback.

✔

  • Increased user satisfaction and loyalty.
  • More efficient task completion and lower error rates.
  • Better product understanding and reduced support costs.

✖

  • Design decisions are context-dependent and not always transferable.
  • Compromises required between aesthetics, performance and accessibility.
  • Thorough user validation can consume time and budget.

  • Task completion rate

    Percentage of users who successfully complete a defined task.

  • Time on task

    Average time users take to complete a task.

  • Error rate

    Proportion of interactions that lead to errors or drop-offs.

Checkout optimization in e‑commerce

Redesign of the checkout flow to reduce dropouts by simplified forms and clear error messaging.

Banking app onboarding

Progressive onboarding with contextual help and staged feature reveals to increase activation.

Internal analytics interface

Design of a dashboard with customizable widgets and role-based access to improve operational decisions.

1

Conduct user and context research

2

Create and validate low-fidelity prototypes

3

Develop a design system and components

4

Implement and test with real users

5

Capture metrics and iterate improvements

⚠️ Technical debt & bottlenecks

  • Hard-coded styles and missing design tokens.
  • Inconsistent component implementations across apps.
  • Missing automated UI tests for core flows.
Performance bottlenecksLegacy system integrationSkills gap in UI/UX
  • Using modal dialogs for all information.
  • Using color as the only distinguishing cue.
  • Building forms without progressive disclosure of fields
  • Skipping usability testing and relying on assumptions.
  • Optimizing only for desktop and neglecting mobile use.
  • Prioritizing functional requirements over user needs.
Interaction and interface designVisual design and prototypingFront-end implementation and testing
User goals and tasksAccessibility and regulatory requirementsPlatform and performance constraints
  • • Device and screen diversity
  • • Compliance with accessibility standards
  • • Technical interfaces and API limits