Simple Is Not Easy: Flat Design and Its Effect on User Interface Design

When simple became the standard

Look at almost any website or app today and you will see the same visual language: plain shapes, solid colours, clear type and plenty of white space. Wasef Qadah's paper starts from this observation. Today's digital design, he writes, is saturated with functionality and simplicity, and it rests on user studies as much as on graphic craft.

The timing matters. In 2020, Covid-19 sharply increased competition between digital products and services. In that market, a product succeeds first of all through a design that catches attention, is easy to use, and helps people understand what the service offers. That pressure pushed the industry towards user-friendly trends built on simplicity, and flat design is the best known of them. Microsoft made it mainstream when it brought it into Windows 8, and by 2019 it had become the most used design trend (Cousins, 2019).

The paper adds a caution: flat design looks simple, yet getting it right takes effort and thorough understanding before any screen is drawn.

The question

The paper asks how flat, simplified design affects user interface (UI) design. It answers through a review of the design literature and a closer look at a few real interfaces.

How it was studied

This is a review paper. It brings together writing on flat design, skeuomorphism, minimalism, Material Design, UI design and functionalism in design. It then applies these ideas to three popular Turkish websites, chosen from a list of the country's top sites: the news site Hürriyet, the classifieds and e-commerce site Sahibinden, and the e-commerce site Hepsiburada.

What flat design is, and where it came from

A two-dimensional style

Flat design keeps elements, typography and flat colours to a minimum. It is called "flat" because it works in two dimensions: colour and areas, with no shadows or effects. It appears in websites and apps, but also in posters, covers and other printed work.

Older than it looks

The paper traces flat design to three movements: the Swiss style, the Bauhaus and modernism. The strongest influence is the Swiss style, led by Josef Müller-Brockmann and Armin Hofmann of the Basel School of Design. Its core values were simplicity, clarity and objectivity, and it brought sans-serif type, grids and asymmetric layouts. In the conclusion the author stresses that these ideas have been in use since the 1920s under the name "Swiss style", so flat design is neither a new trend nor an eternal one.

The swing away from skeuomorphism

Before flat design came skeuomorphism: interfaces that imitate real-world objects to help users make the move from analogue to digital. It peaked with the first iPhone's glossy icons and rich textures, a direction Steve Jobs promoted and others copied. Flat design takes the opposite route, favouring quick delivery of information. Microsoft brought it into Windows 8, and Apple joined the flat side with iOS 7, deliberately leaving its earlier skeuomorphic designs behind.

Not the same as minimalism

The paper draws a clear line: flat design adopts a minimalist approach, but it is not minimalism. Whether to use it depends on the user experience being designed and on how users work with the product.

Flat 2.0

Flat design did not stand still. It evolved into a "semi-flat" style, also known as Flat 2.0, which brings back a few realistic touches such as soft shadows. Drawing on Nielsen Norman Group's analysis (Moran, 2015), the paper reports that this updated version is better for the user experience: it keeps the visual simplicity without giving up meaning. Apple, Microsoft and Google each built design systems that grew out of flat design; Google's Material Design for Android adds gestures and natural motion that echo real-world objects, aiming to reduce cognitive load and make interfaces more predictable.

Who it suits

Citing Dollaghan (2016), the paper notes that flat design is more popular among younger people than older adults. Younger users move faster through flat designs, yet they can also struggle to understand the interface.

Why flat design spread

The paper ties the rise of flat and semi-flat styles to fast technical progress and sharper digital competition. Speed is a clear example. A study by Akamai and Gomez.com found that half of users expect a site to load in two seconds or less after they click, and that slower pages lose visitors or leave a poor impression. Search engines also put mobile-ready pages first, so mobile-first and responsive web design are no longer optional.

The paper also links this to functionalism, which reaches back to the Roman architect Vitruvius and his principle of utilitas: a design is judged by the need and function it serves. A useful yardstick here is the design hierarchy of needs (Braunstein, 2017), which starts from functionality, reliability and usability before it reaches proficiency and creativity.

What good UI design asks for

The paper defines UI design as making the interaction between person and product as simple and efficient as possible. Good interfaces let people finish their task without needless complications or drawing attention to themselves. Aesthetics matter: they can make people feel better about a product. But, following Norman, they can also increase or reduce people's ability to use the interface's functions. So the design process has to balance technical function with visual elements.

Three Turkish websites through a flat lens

• Hürriyet uses a simple logo and a simple interface that orders content by importance and relies on white space. Its elements are overcrowded, but overall the design is flat.
• Sahibinden uses flat design in its shapes, layout and logo. The design is simple, though the site has ease-of-use problems.
• Hepsiburada, compared in its old and new versions, is a site people use every day. Flat design suits it because users need to find products, use the site easily and browse quickly.

The lesson: a site can be flat and still crowded or hard to use.

What this means for designers and teams

• Treat design as a functional tool. Flat design pushes UI designers to judge their work by the value it brings to users, not by aesthetics alone. Many feel this shifts their focus towards user experience, to the benefit of business and customers.
• Know the fundamentals. A flat style built without a grasp of design basics can look careless and unbalanced.
• Ask users first. Research what users want and gather their input before relying on any standard UI approach. Flat design is one option among several, not the only route.
• Do not trade usability for looks. Taste in aesthetics changes and will keep swinging between extremes, but usability directly affects people's productivity. Every design decision should weigh the functional side of form.

Limits

The paper is a literature review with descriptive observations. It does not include user testing or measurements of its own. Many of its sources are web articles from the design industry, and its examples cover three Turkish websites at one point in time. Its conclusions are best read as a framework for thinking about flat design, not as tested results.

Conclusion

Flat design returned because digital platforms needed fast, functional and clear interfaces. Its challenges remain: when sites become overly simple they start to look alike, and that may open the door to newer, more extreme trends. Flat design is a simplified approach to UI design whose aim is to reduce complexity and so improve the user experience, but it should be applied with balance, alongside other approaches such as Material Design.

About the original study

Qadah, W. (2021). Flat Tasarım Yaklaşımını Kullanıcı Ara Yüzü Tasarımında Üzerinden İncelenmesi [Examining the flat design approach through user interface design]. İstanbul Arel University, Graduate Education Institute, Proficiency in Art programme. Available on ResearchGate.