Wizard of Oz Prototyping: What It Is, How & Why It's Done

To understand the concept of Wizard of Oz (WoZ) prototyping, let’s first talk about what we mean by a prototype. Essentially, and for our purposes, a prototype is an early model or release of a website or app built to test a concept, process, or function. 

Just like the wizard pulling the strings behind the curtain in The Wizard of Oz, a design team can fake features so that the user thinks that the responses are computer-driven when they are actually human-controlled so they’re testing a simulation of the functionality. Once you know the important functions, you can then refine them through more in-depth user testing.  

WoZ prototyping is often used in rapid development — the quick creation of a full-scale model. The aim is to improve the user experience (UX) and can be helpful for user interface (UI) design and usability. You can learn more about UX, UI, and usability.

Testing new websites, redesigns, or apps can be a time-consuming process, and often costly. WoZ prototyping aims to reduce the amount of time and money by testing functionalities not yet implemented. You can determine which are necessary and which are not by faking the functionality you want to test with your users.

The Wizard of Oz methodology is an easy way to test a user’s interaction with a website or app. It makes it possible to test a concept or design by having a moderator lead a face-to-face session with each user. 

You then have a designated “wizard” behind the scenes who controls the responses sent to the user. This makes it appear that the responses to the user are a result of the interaction with the technology itself.

When it comes to any testing methodology, there are those suited to some situations but not for others. So it makes sense that the Wizard of Oz methodology isn’t ideal testing for all situations. 

What’s the best use then? 

It’s best used when there’s a need to simulate digital systems like websites or apps, and especially for artificial intelligence (AI) and augmented reality, as well as testing out new functionality. 

It can help designers and developers first learn if an idea is useful and wanted before investing a great deal of time and money in coding.

This type of testing can also help ensure that your design concept works as intended, so it’s ideal for UI design. And, it can help determine if users are able to use your product as it’s intended, which benefits your UX.

Before you begin WoZ testing, you need to have a solid understanding of what functionality you wish to test. The functionality you’re testing will help determine the prototype design. It will also allow you to create the scripts necessary to conduct the testing. So, begin by defining what you want to learn or explore from the testing.

When you know what you’re testing and why you can begin to design your prototype and decide how you want it to simulate the functionality you’re testing. Will a wireframe work or maybe you need a simple digital version? How will you simulate the responses for the user? What’s the role of the wizard?

The key to WoZ prototyping lies in building the prototype. The prototype should be easy to use and allow the wizard to quickly respond to the tester’s actions, ideally with a single click. 

In order to build the prototype, you need to know what functionality you want to test and then make the prototype fake the functionality. It should give the user a realistic experience with their interactions as if they were interacting with a website or app. 

To make the process run smoothly, you’ll also need to develop a script that gives directions for what’s to take place, a designated person to play the wizard role, and your tester who plays the role of the end-user.

Part of figuring out how to simulate functionality involves identifying what tools and technologies you might use. You may not have to reinvent the wheel here, simply take advantage of existing tools such as email systems, instant messaging, Powerpoint presentations, or interactive wireframe tools like Adobe XD.

In order for WoZ methodology to give you answers, you need to set forth testing protocols so you can make sense of what you’re observing or the overall test results and what they mean. Define how you will observe, what type of data you want to collect, and how you plan to collect and record that data.

Typically, the team involved in testing can differ depending on your product, organization, and a host of other criteria. However, there are a few specialists that should always be involved in this process. Here they are: 

WoZ methodology can be used for almost any interface to aid in UI design. It works well for testing out new websites and apps. This type of testing can help designers and developers better understand navigational needs, how the user expects the technology to behave, and pinpoint issues with new functionality. 

WoZ methodology is also ideal when testing out AI-driven experiences. This is because the range of responses can be almost impossible to replicate through traditional prototyping such as wireframes or mockups.

The process for WoZ methodology is dependent upon what you’re testing, the goal of your test, and the level of fidelity of your prototype, which will affect how involved the wizard will be during the testing process. 

In order for WoZ methodology to give you answers, you need to set forth testing protocols so you can make sense of what you’re observing or the overall test results and what they mean. Define how you will observe, what type of data you want to collect, and how you plan to collect and record that data.

Not all prototypes are created equally nor created as realistic as the final product. This is where the fidelity of the prototype comes into play. 

Fidelity refers to the degree to which your prototype reproduces the state and behavior of the real-world feature or condition. It’s basically the measure of the realism of the prototype. The fidelity can vary in the areas of the content, design, and interactivity and is broken down into three levels: low, medium, and high.

WoZ prototyping has many benefits, especially when it comes to improving UX, UI, and usability. It can benefit your UX design, which is crucial in retaining your end users. On top of that, WoZ prototyping can also save you time and money. 

You’re able to test functionalities without committing to extensive coding and development. This means you can test quicker and more frequently as you make enhancements and improvements to your product. 

When you’re able to better work out the kinks in the early stages of development, you’ll end up with a much higher quality product in the end, which your customers will appreciate.