The 3 foundations of product design

All products have one thing in common — they were created to bring value to someone. But how is the value that make products irresistible built in and then beautifully optimized?

Whether you’re a designer, executive, engineer, investor, co-founder or just a consumer of products (which we all are), you’ve felt the pains and joys that come from the products that surround you. Now, although it’s easy to feel when a product is good or bad, it’s slightly more difficult to articulate the reasons why. As I’ve experienced products both from a consumption standpoint as well as a design/architectural standpoint, I’ve settled on 3 fundamental principles that now guide my process for building and critiquing quality products — function, usability & aesthetics.

#1 Function

Function is, I believe, the single most important foundational starting-point for any and all product design strategies. Function solves problems. Function enables people to do things that would be more difficult to do otherwise. Function is the substance that breathes life into the value proposition of a product. How valuable can a product be that doesn’t offer any value?

The first step in focusing in on function is to clearly articulate the product’s value proposition. If customer needs are unclear, how can you expect to build something they value? You know you’re focused on function when you’re asking yourself and solving questions like:

  1. Who is my customer? (Write it down.)
  2. What are their needs? (Write them down.)
  3. What features does this product require to address each need? (Write them down.)

*When I make a reference to “features” throughout this article, it’s not meant to imply anything specifically. The term is used to reference anything that is consumed by a users in a product — such as a flow, a piece of data, an actual part of a physical product, a user task, etc.

By defining the value proposition and making a clear correlation between user needs & product features, you will be able to tell the story of what your product does. This is function.

Without clear & relevant function, a product has no initial or lasting value — regardless of how easy it is to use or how nice it looks.

It’s clear that a product needs to function in order to provide value. But function is still only the starting point. Let’s say you’ve built a product that people are using because it solves a problem and/or meets their needs — fantastic. Does that mean you’ve “won?” Maybe — but probably not. The next biggest risk you face in building your product is that you don’t solve the problem good enough & customers leave (and tell others until no one is coming or staying). What can you do to mitigate the risk of them going to another product that solves the same problem? That’s where usability comes into play.

#2 Usability

The principle of usability is the practice of identifying & removing barriers between the user and the value they are trying to realize with/within a product. Usability seeks to optimize how products are arranged, structurally organized and visually laid-out for enhanced user consumption. There are three things to consider when focusing on usability — timing, frequency & context.


When does a user logically need this feature? Timing is core in achieving “progressive disclosure” with elements of a product. Every feature isn’t needed all of the time. Introducing a feature at the wrong time reflects an inattention to detail, leaves users confused & ultimately deteriorates user confidence in a product. Understanding feature timing helps product designers know when the best/most logical point-in-time would be to introduce a feature to customers.

Here’s an example of great usability timing pulled from Gmail.

Not all of the functions of the task bar are relevant at all times — so Gmail hides the options until they are relevant.

Now here’s an example of poor usability timing pulled from Microsoft Outlook 2013.

While all of the options are not needed all of the time, Outlook decided that you should still see them all! Hurray!(?)

Side note: I nearly cried (for joy) when I found out the company I most recently joined used Gmail Apps for email…


How often do customers use this feature? Why do you think the “compose” button in your email is the largest, most prominent button on the page? It’s because it’s used the most. By understanding how often users engage with a specific feature, designers can modify the priority and prominence of the feature to give it the appropriate level of accessibility.

Another example from Gmail — the frequency of the task “composing an email” was higher than any other task so it made sense to draw the most attention and ease of accessibility to the compose button:

Thank you Gmail for making it easy for me to do the things I do most in my email experience — i.e. Composing an email. Great example of a recognition for frequency in my email experience.


Where does a user look to find this feature? It’s never fun trying to find something within a product and ending the search without success. When features or elements of a product are not visible on the surface, it’s important to carefully organize related features and elements together for simple discoverability. Be sure to 1) understand your customer’s level of technical comprehension — making no assumptions about where they “should be looking” and 2) use design conventions where possible — give users a familiar visual queue on where they might go to look for a feature.

It’s natural to assume that I could initiate a new message from the same place I see the most recent message from others — this is an example of good contextual usability.

Make your own list of features found within your product — “what are all of the things it does?” Next to each item, determine the timing, frequency and context of each feature. Do you know what your customers do most often with your product? How might you modify your product to better facilitate the features your customers use most often? Now consider those same features and the number of steps that they require the user to perform — both the steps getting to that feature and also the steps that that feature itself requires. Are the features your customers use most often also the features with the most steps? How would shortening the process & removing excess steps of highly-trafficked features play out with your users?

Good products solve my problems. Great products solve my problems with less effort (from me).
While both result in a rolled-down window, which is easier to use? Just because a product solves a problem (window down) doesn’t means there are no more problems to solve (how hard it is to roll a window down).

Now that a product functions and is intuitive to use, how can you ensure consistency in the messaging of that experience across features within the product? With the wrong visual messaging, great products can be misleading, sloppy and difficult to trust (impede user adoption).

#3 Aesthetics

Aesthetics refers to the visual language that represent a product — what it looks like, how it is presented and the messages it conveys to users. The visuals are the front-lines of the messaging of a product that precede & transcend product usage. Aesthetics play the largest roles in 1) how users learn to engage with the product and 2) shaping how a product is perceived.


When users engage for the first time with a product, they’re learning. They’re trying to figuring out where they are, what to do, where to go, what controls what, what not to touch, etc. Effectively designing for engagement aesthetics will remove confusion and defuse such questions as quickly as possible. Whether we admit it or not, the barrage of features & elements that make up a product are all sending messages to its users. It is important that messages conveyed from visual elements are consistent across the experience and work for the user in helping them adapt to and understand the product. Here are three aesthetic design considerations around product engagement — transformation, navigation & meaning.

  1. Aesthetics have an influence on product engagement by how they can aid in teaching users about which elements, when engaged, result in a functional transformation or change. At the most basic level, users are engaging with the product to perform tasks and accomplish things. For example, it’d be important to consider how to visually convey the difference between the “Power your car on/off” button and the “Power your stereo on/off” button in a vehicle. While both are buttons that, when engaged with, result in functional transformation — something changing states — having a driver accidentally press the “Power your car on/off” while driving would be a terrible mistake which can be prevented if considered in the design process.
  2. Aesthetics also have an influence on product engagement by how they can teach a user to navigate around a product. Users should be guided visually on how to explore the product without fear of triggering a transformation. For example, say we are examining two buttons that have the same visual treatment on a social website. The first is a “Like” button that, when selected, causes a transformation; another user is notified of the “Like,” the post is now visible to others on that individual’s “Liked” section, etc. The second is a “Share options” button that, when selected, simply navigates users to a page where they can then select a method of sharing the post with others. Although designing these options to look the same may “look nice,” the message that “these options look the same so they will react the same way when I click on them” could be present and, in this case, is misleading. Leading users to believe that two buttons will respond in the same manner based on how they are visually designed will cause potential mistakes or at least cause the user to need to pause & think about whether something is different between them in the future. This type of critical-thinking is an unnecessary level of problem solving (friction) that we designers push onto users — if we designers don’t think it through for users, they will have to think it through themselves, with frustration. Aesthetic navigation also extends to structuring effective visual/information hierarchy & offering explicit clarity in direction for users in tasks that possess several sequential steps.
  3. Lastly, aesthetics have an influence on product engagement by how they can teach users the meaning of things. Visual elements can be used specifically for communicating positive and negative outcomes. For instance, the color green, conventionally, can be interpreted to mean both “good” and “increase.” “Good” is understood to be a desirable outcome. “Increase” is understood to be a signal of change — whether that change be good or bad. The rising of a stock price may be a “good” thing for some and simply an “increase” for others. If a designer chooses to use the color green to represent “good” within one aspect of the product, using green in to mean “increase” in a separate element of the same product experience may cause confusion.
The “Like” and “Share” buttons are styled the same leading consumers to believe that the outcome of interacting with each will result in a comparable outcome which is not the case. The “Like” button is causing a functional transformation while the “Share” button is simply a form of navigation.

Whether you’re designing elements of a product for purposes of transformation, navigation or meaning, the most important thing to remember is that if/when rules applied to one intersect or overlap with another, user will be confused and fumble while using the product. Following & being sensitive to common design conventions aids and enhances the visual language of your product. More importantly, leveraging research to best understand what conventions exist specifically for those who the product is being designed for can dramatically lower the learning curve of new users because they are engaging with visual elements familiar to them.


Perception is a powerful force that can help or hinder the success of a product. Perception extends into product pr, branding, marketing and advertising initiatives. While the discussion of pr, branding, marketing and advertising are not direct principles of product design, there are specific ways the design of the product can and should impact these efforts.

  1. Aesthetics have an influence on product perception from the way the branding can aid in building an intellectual and emotional relationship with the product. Do users identify themselves with the product? Do they feel it for them? How are they reacting with each touch-point with the product? Do they trust the product? These are all questions that can positively and negatively be influenced via the products branding.
  2. Aesthetics have an influence on product perception via pr, marketing & advertising by what consumers are lead to believe the product does and can do for them before they use the product. How does this relate to product design? If consumers are lead to believe that a product does one thing before the interact with it when, in fact, it does something else, they are likely to be confused and potentially upset that what they were lead to believe was just not true. How the product is marketed to consumers needs to align with what the product does in reality — pretty simple.

Whether your designing for a product’s aesthetics around engagement or perception, one goal to strive for is consistency. Consistency is central to trust. You wouldn’t expect two completely unrelated commercials for the same product promising different things. Similarly, colors and styles of a product’s commercials should be continuous with engagement initiatives like the colors and styles of the product’s website. In the web-world, one such tool used to maintain design standards across products & design initiatives is called a “Style Guide.”

Things to consider…

Don’t do the right things at the wrong time.

While each of us sometimes jump the gun and think immediately on “how the product will look,” focusing on the right things at the wrong time can cause serious delay and lack of focus. Effectively and efficiently coming to a conclusion about what hierarchy, layouts, flows and visuals I need to bring the product together, it’s important to first consider why consumers need this product and what they will do with it — function. If I skim over the functional and usability dynamics of product design and go straight to how a product will look, how will I know what visuals fit the use-cases of the product? I may fall in love with visual elements and components that don’t really work for the product in the right ways when I later consider what the product will do and who will be using it. If I jump straight to how a product will look before anything else, I’ve immediately demonstrated that I care less about the value it brings end users than I do about how slick it makes my portfolio look.

Thoroughly thinking through a product’s function & usability before jumping into visuals gives me clear direction when I build products. Also, when the visuals of a product are questioned (which is likely always going to happen), being able to fall back on the functional and usability reasonings behind a product’s visual design decisions lends confidence and persuasiveness when selling designs to clients and teams.

Don’t think about the font or color you are going to use before you consider what the product needs to do to make customer lives easier.

Function trumps usability. Usability trumps aesthetics.

While I have unmatched sympathy for dedicating energy to upholding an existing visual standard for a product, slap me if I ever try to turn down a new design that will make the product easier to use simply because I fear it will negatively impact the visuals of the product.

How a product looks should never be a barrier to improving a product’s usability. Similarly, how a product is used should never be a barrier to improving the functional value of a product. The idea here is to simply acknowledge the fact that consumers care more about function & usability than they do about how the product looks and to help us recognize those situations where we find ourselves contradicting this fact. We designers won’t be applauded for keeping a product looking perfect. Instead, we’ll be applauded for making users lives easier and less painful. The true test comes when you’re asked to uphold an exceptional visual design standard without undermining function & usability aspects of a product.

In conclusion

Designing products is not a simple thing. Building something that solves problems, is easy to use and is clear to understand is as much of an art as it is a science. Recognizing the place for function, usability & aesthetics in the product design process will enabled designers to focus on the right things at the right time, help them work more efficiently, allow them to set the right priorities and perspective, and, most importantly, help mitigate the risk of producing less-than-outstanding products.