A Persona Development Case Study

A hypothetical case study of designing voice personas for two fictional airlines

In this brilliant and thought-provoking talk at Google I/O ’18, Walter Brill narrates a hypothetical case study of developing personas for the voice assistants of two fictional airlines.

Please note: Developing personas for voice assistants is vastly different from developing buyer personas for a business. However this well-crafted case study will help us understand the basic motivations behind designing personas as well as the process used to develop them.


Within seconds of hearing a voice, we mentally assign a personality to it. We attempt to infer the age, gender, level of education, locale and the “register” of the person behind the voice. We also attempt to infer the intelligence, trustworthiness and likability of the person. Surprisingly we do this even if the voice is that of an artificial construct such as the Google voice assistant.

People have very high expectations of what an Artificial Intelligence-powered voice assistant is capable of. Thus it is  important to carefully design the persona of the voice assistant. Imparting a persona  will keep what the voice assistant says, consistent and clear.  Otherwise it can appear fractured and if the persona is fractured, people will not trust it.


The Persona Development Methodology

So how does one go about designing this digital employee, the voice assistant?

Let’s consider two fictional airlines to see how the persona building process is carried out.

  1. Our first airline is Important Airlines who go by their tagline, “We’re important and we will get you there”. It is a national carrier - traditional, straight and without any frills.
  2. The second airlines we have chosen is Millennial Airlines who have a tagline - “It’s an awesome day to fly”. They are fun, whacky and as their name suggests, cater to the millennial audience.

Step 1 - Understanding the Brand

The first step in our persona building exercise is to understand the brand. In this exercise, we not only need to understand the customers but additionally the business - the company, its values and how they want to be perceived by their customers - the brand. To do that we take the following steps.

  1. Interviewing stakeholders - Marketing / Brand / Customer experience
  2. Reviewing the style guide or “brand book” of the company
  3. Reviewing advertising materials - print / TV / outdoor etc.
  4. Experiencing the product ourselves
  5. Visiting the contact centre - The contact centre delivers the brand essence in an intimated manner when they speak to customers, and thus visiting the contact centre will help us know who the brand is
  6. Checking out their social media
  7. Visiting the retail outlets

After examining the above we conclude that the brand attributes of Important Airlines to be the following:

Important Airlines Brand Attributes

Solid, Confident, Expert (they know what they are doing), Reliable, Straight-forward (no frills), Safe


Similarly we deduce the brand attributes of Millennial Airlines to be the following:

Millennial Airlines Brand Attributes

Bold, Hip, Fun, Friendly, Exciting, Delightful


Step 2 - Understanding the Customer

This step is central when we go about developing buyer personas too. We attempt to understand the customers of both airlines with the following approaches:

  1. Reviewing the context and customer journey
  2. Studying customer demographics - Where do they live, what do they like
  3. Learning the frequency of engagement
  4. Understanding customer expectations and needs

Typically people like to be mirrored, to interact with someone who is like them, someone they can relate to. Keeping this in mind we endeavour to build a persona that can effectively mirror our customers.

After studying the customers of both airlines we decide that we have deduced the following about them:

Profile of Important Airlines Customers

Mid 30s and up, Business travellers, High value (business class), Frequent flyers


Profile of Millennial Airlines Customers

Late teens to mid-30s, Holiday makers, young families, Budget conscious, Infrequent use


Step 3 - Understanding the task

For this case-study the voice assistant will be entrusted with a simple task - to deliver flight information to customers of the airlines when they demand it.

Step 4 - Choosing the Medium for the audio

Since we are developing a voice assistant we find ourselves presented with a unique decision to be made - Using Text-to-Speech (TTS) or custom recordings. We will need to take a decision about which approach is going to be suitable for us. Here is a quick Pros/Cons analysis of either approaches.


Pros - Scalable, Inexpensive, Handles dynamic content

Cons - Limited voice availability, Problems with prosody (the melody of speech) thus affecting comprehension


Custom Recording

Pros - Natural sounding speech, expressive and comprehensible (great prosody), Option to hire any voice actor from around the world

Cons - Not scalable, expensive, Cannot handle dynamic content

As an example of what custom recording can do for us, we can examine the popular meditation app, Headspace. Headspace decided to use custom recording using Andy Puddicombe’s voice. Andy is a meditation teacher, public speaker and is also the co-founder of Headspace. The decision has paid rich dividends and Headspace has come about to be a product with excellent voice narration.

For our case, after weighing the pros and cons of both approaches, we decide to go with TTS, primarily because it will be difficult delivering flight information effectively with pre-recorded, custom audio.

Step 5 - Creating the appropriate personas

Now we come to the step where we build the characters who will represent the brand attributes we have established.

At the onset we will need to find the answers to two questions:

What is the register of the persona?

A register is “a variety of a language or a level of usage, as determined by the degree of formality and choice of vocabulary, pronunciation, and syntax according to the communicative purpose, social context, and standing of the user”. ~Oxford Dictionary

Secondly, what is the relationship between the persona and the user?

Peer - a really close friend of mine, Employee - somebody that works for me and does whatever i ask whenever i need it, Advisor - someone who knows more stuff than me, is at a higher level that i am taking information from

We can create three different personas with three different registers and see how well they represent the brand attributes of our airlines.

A Control and Affiliation Chart developed by Cliffor Nass, a renowned authority on HCI, will come handy while we attempt this.

Control and Affiliation Chart


After deliberate consideration of the research we did in the earlier steps, we propose the final personas for both airlines.

Important Airlines persona - Terence the Butler

Customers of Important Airlines are high value, business class flyers who are likely to have interacted with a butler, someone with the level of gravitas usually displayed by butlers. Our recommended persona is a concierge character that customers of Important Airlines can trust.


This is how the persona of Terence Butler relates with the brand values of Important Airlines.

Important Airlines Persona Summary - Terence Butler


Next, we develop a monolog for our persona. The monolog is a paragraph or two of something the persona might tell a friend in a casual conversation about any subject, ranging from what they did on the weekend to why they painted a room a certain color.

Important Airlines Monolog - “Bow Tie”

“I quite enjoy this occupation. It’s extremely gratifying to know that one is indispensable. If Sir is stepping out of an evening I shall have prepared his dinner jacket and accessories and I shall of course assist him in tying his bowtie. The work of a gentleman’s gentleman is never done”.

Note how formal his language is.

After that we develop a sample dialog for Terence Butler.

Important Airlines Sample dialog

Wally: OK Google, talk to Important Airlines

Google Assistant: Getting Important Airlines

Important Airlines: Good morning, you are through to Important Airlines, am I speaking with Wally?

Wally: That’s right

IA: Thank you. And do you require information regarding your flight to London today?

Wally: Yes

Millennial Airlines Persona

This is the persona we propose for the the voice assistant of Millennial Airlines - Helen Highwater


This is how the persona of Helen Highwater relates with the brand values of Millennial Airlines.

Millennial Airlines Persona Summary - Helen Highwater


Millennial Airlines Monolog

“I use everything and believe me, when you deal with passengers, there’s endless amount of material, like the woman who was going to Boston but her luggage was on its way to Austin, or the parents off on holiday who each expected the other to bring the kids to the airport! Then there’s this guy who believes he deserves an upgrade because he was in some obscure rock band from 20 years ago or something!…let me tell you, it’s great training for a stand-up and i get paid for it and if i can deal with them there, there isn’t a heckler in the world who can bother me”

Millennial Airlines Sample Dialog

Wally: OK Google, talk to Millennial Airlines

Google Assistant: Getting Millennial Airlines

Millennial Airlines: Millennial Airlines. It’s an awesome day to fly. Is this Wally?

Wally: Yup

Millennial Airlines: Great, do you want info about your flight to London today?..

Wally: Yes

Positioning on the Control and Affiliation Chart

Where would both of these personas lie in this chart?

Terence is an introvert

Helen is way towards the right at friendly


Step 6 - User Testing

Testing with real users will tell us how accurate we got it in our first try. While this topic is outside the scope of this case-study, this is nonetheless a vital step in ensuring we have a continuous feedback loop that takes us closer to the most accurate personas.


This is a summary of the approach taken towards developing the persons.

  1. Review your action
    1. Is the persona clearly defined
    2. Is it directly representative of the brand, the user and the task?
  2. Define the persona
    1. Learn about the brand
    2. Know the user
    3. Understand the task
    4. Define appropriate characters
  3. Bring it to life
    1. Create, record, and review audio monologs and sample dialogs (custom recorded or TTS)
  4. Test - Test your action with real customers to derive data and proof points for stake holders. Test with real customers, low fidelity prototypes, dialog flow etc. You need some data points about whether customers, real users felt this was the right for the brand

Now that you have gone through the persona design process for voice assistants, you can read about developing buyer personas for your business.