TightWind is written by Kyle Baxter. Stay Hungry. Stay Foolish.

Last week, Marcelo Somers wrote that when designing a product, you should begin with the experience, not the features it has. You should think primarily about what the product’s purpose is—that is, what is the high-level task in someone’s life that it accomplishes. Marcelo calls this what the product is being hired to do, and I think that’s a great way of thinking about it.

This distinction between designing for a product’s purpose and designing based on its features may seem trivial, so let’s consider an example to illustrate it: the MP3 music player. Here are the music player’s central features:

• Plays back audio files through a 3.5mm headphone jack
• Allows user to put audio files on the device and remove them

Here’s the music player’s purpose:

• Conveniently listen to my music wherever I am

Note how much more the purpose guides your design decisions than the feature list. How should the user physically interact with the device? How should their audio files be organized? What should its physical design be? I don’t know. The feature list just tells you what it should literally do, not what it should accomplish.

But if you start with the music player’s purpose, it begins to answer a lot of these questions. How should the user interact with the device? In a way that’s quick and simple to do, so they can go back to what they were doing as quickly as possible. How should their audio files be organized? Since it’s for playing their music, they should be organized by how we think of music—artist, album, genre, et cetera, and they should be organized in such a way that it’s fast to find exactly the album or song I want, because I’m primarily using it while doing something else. How should it physically be designed? Since it’s for listening wherever the user is, it should be as compact as possible, and it should have a large enough screen for moving through the user’s music.

Focusing on the product’s purpose does even more than begin to answer the very literal design questions, though. What’s truly important is it frames the entire product with a very simple, very easy to understand intent. That intent—in this case, “conveniently listen to my music wherever I am”—is a sort of maxim used to guide and judge the entire project. It’s a lense to look at the project through, and it tells you whether you are succeeding or not. Rather than design each separate part of the product as an autonomous piece separate from the rest, the purpose integrates every part of the product, however small or large, into a cohesive whole.

That frame is what allows customers to immediately understand what a product is for, how it fits into their lives and how it would make their lives better. It does that because every bit of the product was designed to serve that purpose, and when a product’s been designed that way, it’s like a very clear thesis: people see what it’s for from the product itself. They don’t have to figure out what it’s for and what they could use it for, because it’s immediately obvious.

So when considering creating something new, don’t think about it as what it literally does. Think about what it will accomplish for people. Make this your project’s defining thesis, its reason for existing. And once you’ve settled on what that purpose is, design ruthlessly for it. Don’t compromise it. “I can listen to all of my music wherever I am” is much more powerful than “a device which stores and plays audio files.”