Choosing a Look and Feel: My Dive into Material, Fluent, and UI5

For a course on Human-Computer Interaction, we were tasked with building a prototype for a new application. A big part of our grade was the user interface and overall user experience. This meant I had to move beyond default HTML buttons and choose a real design system and component library.

I quickly fell down the rabbit hole of design philosophies and ended up comparing three of the biggest players: Google’s Material Design, Microsoft’s Fluent Design, and a more specialized one I discovered called SAP UI5.

Material Design: The Ubiquitous Standard

The first one I tried was Material Design, using the popular MUI library for React. You can’t escape Material Design; it’s everywhere, especially on Android and Google’s web apps.

What I liked:

It’s incredibly comprehensive. There’s a component for everything, and the documentation is exhaustive. You can build a complex, good-looking application very quickly.
It feels familiar. Because it’s so widely used, building with it feels like you’re creating something that users will intuitively understand.

What I found challenging:

It can feel a bit generic. Because it’s so popular, it’s sometimes hard to make your application feel unique without a lot of custom styling.
It’s very opinionated. Material Design has strong ideas about how things should look and behave, which is great for consistency but can feel restrictive if you have a different vision.

Fluent Design: The Modern & Airy Challenger

Next, I explored Microsoft’s Fluent Design. As a Windows user, I was familiar with its look and feel—the subtle transparency, the focus on light and depth.

What I liked:

It’s beautiful. Fluent feels very modern and clean. The use of acrylic materials and motion gives it a sense of polish that’s really appealing.
It’s great for information density. It seems to handle complex, data-heavy interfaces really well, which is a big plus for more “serious” applications.

What I found challenging:

The ecosystem is less mature. While there are good libraries out there, the community and the number of available resources are smaller than Material Design’s.
It feels very “Microsoft.” This isn’t necessarily a bad thing, but the design language is so tied to the Windows ecosystem that it can feel a bit out of place on other platforms.

SAP UI5: The Enterprise Powerhouse

This was the wild card for me. I stumbled upon SAP UI5 while looking for design systems specifically for business applications. It’s not as well-known as the other two, but it’s a powerhouse in the enterprise world.

What I liked:

It’s built for business. UI5 is designed from the ground up for complex, data-driven applications. It has powerful components for tables, charts, and forms that are a step above what the general-purpose libraries offer.
It’s incredibly consistent. It provides a rock-solid, unified look and feel that’s perfect for a suite of business tools.

What I found challenging:

The learning curve is steep. UI5 has its own way of doing things, and it’s deeply integrated with the broader SAP ecosystem. It’s not something you can just pick up in a weekend.
It’s not very flexible. It’s designed for a specific purpose, and trying to use it for a general-purpose consumer application would be like trying to use a freight train to go to the grocery store.

My Decision for My Project

In the end, the choice came down to the specific needs of my project.

If I were building a standard consumer-facing mobile or web app, I’d probably stick with Material Design for its familiarity and massive ecosystem.
If I were building a modern, data-rich desktop application, especially for Windows, Fluent Design would be a very strong contender.
But for my project—a prototype for a complex, data-heavy enterprise dashboard—I actually chose to build with the principles of SAP UI5 in mind. Even though I didn’t use the full framework, its focus on data-centric components and enterprise workflows gave me a great blueprint for how to design my application.

This exploration taught me that a design system is more than just a collection of pretty components. It’s a philosophy, and choosing the right one depends entirely on what you’re trying to build.