Scenarios answer, “How do they use it?”
Personas, as awesome (and ofttimes debatable) as they are, help answer only one of the fundamental interaction design questions: Who are the users?
Another question is as important: How do they use it? and the primary tool to answer that is scenarios. Read a quick example of one below, for a speculative home lighting solution.
Jane gets a midnight snack
- Jane is on holiday, staying at a friend’s place in Auckland. Hunger wakes her at midnight, so she makes her way to the dark kitchen, where she sees the softly illuminated dimmer switch.
- She doesn’t want to wake her hosts, so she sets the brightness to dim, before turning it on.
- In the dim light she is able to find a fruit bowl for a banana before flipping the light back off and returning to the fold-out bed.
Scenarios like this one are stories that tell how your personas use a product or service over time to accomplish tasks or better yet, goals. (Note: For brevity, “product” will be used for “product and service” throughout the rest of this post.) Scenarios don’t get as much airtime as personas, but they’re the handle to the hammer, as my colleague Jenea says, so consider this a quick-read primer.
- For most products there are many scenarios describing use by many personas.
- Individual scenarios are cinematic in that they don’t wander down alternate paths and spend time on what might happen, they illustrate one particular experience.
- They start as simple stories, but evolve along with and alongside other tools like flow charts, static mockups, and demos. We privilege scenarios over these other tools because they keep us focused on the important things that most determine the long-term desirability of our products: personas, contexts, usability, and utility.
- The many scenarios that you develop overlap to form a bigger picture of the whole system. Those other design tools are top-down, and carry the risk of encouraging choices that favor the system at the cost of the user experience. Even demos, which can give you a very rich sense of what a product will feel like to an individual user across time can’t keep you focused on context and personas.
Each scenario has four basic parts.
- A title that identifies the persona and describes the arc of the story.
- A beginning, that places the persona in a context of use, with a problem.
- A middle, consisting of a series of steps that detail what the persona experiences, thinks, and does. Often called the see-think-do loop, each step captures outputs, affordances, perceived meaning and/or emotional impact for the persona, and inputs to the system.
- An end, showing the problem resolved, the personas’ goals met.
One thing to note is that in order to facilitate these design discussions, the language we use for the thing-to-be-designed can be quite vague, or “solution agnostic.” Reading Jane’s scenario you may have imagined a rotary dimmer switch, but it could as well have been a dimmer with a large slide and a small on-off switch below, a rocker switch with a thin dimmer alongside it, a tabletop toggle, or even a custom solution that the designers determined was more appropriate.
That’s part of the point of scenarios. They let you iterate quickly not on design details or microinteractions, but rather on higher-order issues:
- Contexts of use
- The order of operations
- The connections between input and output
- The information to be conveyed by the persona and the system in return
- Necessary affordances of controls
- Emotionally intense stages of a process
- Achieving goals
Once designers come to a set of scenarios that answer these design issues—covering interactions including initial use, routine use, and even disengagement—we can then move to a next medium to design against them, such as a digital whiteboard to sketch proposed interfaces.
In this way scenarios allow designers to play inside a conceptual boundaries that still take into account the contexts of use and help a persona achieve her goals.
This was originally written to be a sidebar to Donna Lichaw’s new book, The User’s Journey. They ran out of ink, so I’m posting it here.