Redefining Clean Interface Design

Interface Examples 

First, I want to introduce two examples for flat minimalistic interface design and two examples of interface which follow the new definition of clean. 

These examples shall make the contents of the article more accessible for the reader. Further, they shall visually clarify what is meant by flat interface design and by the new, redefined design.

The Limitations of Extreme Flat Minimalism (2015–2021)

The flat-design wave sought abstraction: removing visual depth, material cues, and decoration to create neutral, efficient interfaces. However, this approach assumed a high degree of user literacy and pattern familiarity. Research in human-computer interaction and cognitive psychology shows that users rely heavily on perceptual cues, such as depth, contrast, and motion, to understand possible actions. When these cues are removed, users must rely on memory, trial-and-error, or learned conventions.

Problems that emerged included:

• Reduced discoverability of interactive elements
• Increased cognitive load due to ambiguous hierarchy
• Accessibility failures, especially for users with visual or motor impairments
• Emotional flatness and reduced sense of feedback or control (Apple HIG; Apple WWDC 2024–2025).

In essence, interfaces became visually clean but perceptually opaque (Gibson 1979; Sweller 1988; Ware 2013; Norman 2013).

Perceptual Affordances and Cognitive Clarity 

A key concept behind the current shift is perceptual affordance: the idea that users should immediately perceive what actions are possible through visual and sensory cues alone. This builds on foundational work by James J. Gibson and later Don Norman, emphasizing that usability depends not on functionality alone, but on perceived action possibilities (Gibson 1979; Norman 2013; Amazon UX Guidelines).

Foundational theories of perception and cognition articulated in the late 20^th century continue to be explicitly confirmed by contemporary UX research and large-scale design systems. Gibson’s theory of affordances (Gibson 1979), which established that action possibilities must be perceptually available to the user, is directly reaffirmed in modern UX literature emphasizing visible, material, and motion-based affordances (Johnson, 2020; Nielsen Norman Group, 2018–2024). Norman’s distinction between actual and perceived affordances (2013) is operationalized today in platform guidelines such as Apple’s Human Interface Guidelines (Apple HIG), which explicitly encode interactivity through depth, translucency, and motion rather than relying on learned conventions. Sweller’s cognitive load theory (Sweller 1988), particularly the concept of extraneous load imposed by poor information presentation, is mirrored in contemporary design guidance warning against minimal interfaces that shift interpretive effort onto users (Yablonski, 2020; WCAG 2.2, 2023). Similarly, Ware’s (2013) work on visual perception and pre-attentive processing finds direct application in modern design systems such as Google’s Material Design 3 and Material 3 Expressive, which reintroduce color, elevation, and motion to restore perceptual hierarchy (Google Material 3). Together, these modern sources do not revise the original theories. Rather, they confirm and institutionalize them under current technological conditions, demonstrating that overly flat and abstracted interfaces increase cognitive load and reduce affordance clarity, while perceptually grounded design improves usability, accessibility, and user confidence at scale.

Depth, shadow, translucency, color, and motion are not decorative by default. When used systematically, they: 

• Reduce cognitive effort by externalizing structure
• Improve error prevention by clarifying interactivity
• Support accessibility by offering redundant cues beyond color or text
• Align interfaces with real-world perceptual models.

Modern “clean” design therefore reintroduces these elements—not as ornament, but as semantic signals (Norman 2013; Ware 2013).

Apple: Materiality and Spatial Clarity

Apple’s Human Interface Guidelines increasingly emphasize material, depth, and spatial hierarchy. Recent design directions (often described as “Liquid Glass”) use translucency, blur, and layered surfaces to separate interface chrome from content without heavy borders or opaque panels. 

Key characteristics include:

• Translucent surfaces that preserve context while signaling separation
• Subtle motion that explains spatial transitions
• Large, comfortable touch targets embedded in lightweight materials.

This approach preserves minimalism while restoring perceptual affordances. Clean, in Apple’s ecosystem, now means calm, spatially intelligible, and perceptually grounded.

Google: Expressive Clarity Through Systematic Signals

Google’s Material Design 3 and Material 3 Expressive represent a parallel but distinct response. Rather than hiding structure, Google makes it explicit through color, shape, and motion, while remaining systematic and accessible.

Key principles include: 

• Dynamic color systems that encode hierarchy and personalization
• Clear elevation and surface distinctions
• Motion used to communicate state and causality.

Material 3 acknowledges that abstraction without signaling harms usability and instead uses expressive elements to improve recognition and confidence, especially for broad, non-expert audiences. 

Amazon: Functional Clarity at Massive Scale 

Amazon does not publish a unified public design language like Apple or Google, but its interfaces consistently reflect the same redefinition of clean design. Amazon prioritizes clarity, trust, and efficiency at enormous scale (Amazon Developer UC Guidelines).

Observable principles include: 

• Clear visual grouping of actions and information
• Conservative but purposeful use of color and emphasis
• Strong affordances for critical actions such as purchasing and navigation.

Amazon’s design demonstrates that clean interfaces must support decision-making under cognitive load, not merely visual neatness.

The New Definition of “Clean”

The new emerging consensus is: Clean design is not the absence of visual signals, but the absence of unnecessary cognitive effort. Accordingly, a clean interface: 

• Makes hierarchy perceptually obvious
• Signals interactivity without explanation
• Supports accessibility by default
• Feels calm, trustworthy, and responsive
• Uses depth, color, translucency, and motion with semantic intent.

This redefinition represents a maturation of interface design. The insight that extreme abstraction undermines usability, and that perceptual grounding is essential for human-centered systems must spread further. 

Conclusion 

The shift away from ultra-flat minimalism is not a regression, but an evolution. Apple, Google, Amazon, and Siemens demonstrate that modern clean interfaces can be rich without being noisy, expressive without being chaotic, and minimal without being opaque. Clean design has been redefined from visual emptiness to perceptual clarity. 

Key Takeaways

References

Apple Inc. Human Interface Guidelines (HIG). https://developer.apple.com/design/human-interface-guidelines/

Apple Inc. WWDC Sessions (2024–2025) on visionOS, UI materials, and system design.

Google LLC. Material Design 3. https://m3.material.io/

Google LLC. Material 3 Expressive design documentation and updates.

Amazon Developer Services. UX Design Guidelines. https://developer.amazon.com/

Norman, D. A. (2013). The Design of Everyday Things (Revised and Expanded Edition). Basic Books.

Gibson, J. J. (1979). The Ecological Approach to Visual Perception. Houghton Mifflin.

Sweller, J. (1988). Cognitive load during problem solving: Effects on learning. Cognitive Science, 12(2), 257–285.

Ware, C. (2013). Information Visualization: Perception for Design (3rd ed.). Morgan Kaufmann.
 
Johnson, J. (2020). Designing with the Mind in Mind (2nd ed.). Morgan Kaufmann.
 
Yablonski, J. (2020). Laws of UX. O’Reilly Media.
 
Nielsen Norman Group. UX research articles on affordances, flat design, and usability (2018–2024).
 
World Wide Web Consortium (W3C). (2023). Web Content Accessibility Guidelines (WCAG) 2.2.