Use Case 01: Order A Single Cup Of Coffee

Bird's Eye View Of Use Case #01

We’re in the process of designing use cases on the CoffeeBoy UX design structuring plane. Across several posts each use case gets detailed by means of one or more interaction flow chart diagrams as well as explanatory text. In this post we’ll focus on the order a single cup of coffee use case. While the above diagram gives us a bird’s-eye view of this use case, find all details below.

CoffeeBoy Series Schedule

The interaction concept

On the strategy plane we’ve decided that brewing a single cup of coffee should be as simple as possible for our personas. Especially for Bob. Now one way to reach that goal is to adopt an established interaction concept of existing coffee machines, which can be described as follows:

  1. Placing an empty cup below the coffee machine’s nozzle.
  2. Choosing a coffee recipe.
  3. Starting the brewing process.
  4. Monitoring the brewing process until it has ended.
  5. Taking the cup.

We want to adopt this interaction concept because it should be very familiar to Amy and Bob. Of course the first step won’t be necessary with our product as long as there are enough empty cups on the tray.

Often coffee machines allow the user to modify the coffee recipe’s properties, either before or during the brewing process. While we want to also enable our users to modify the coffee recipe before the start of the brewing process (we’ll cover that in the next post), we’ll not enable that during the brewing process. However, in case our users will change their mind regarding their coffee recipe choice after the brewing process has started they’ll get the chance to cancel it and make a new order.

We believe that this use case will be traversed most frequently by our users. For that reason the Single Cup Of Coffee Order view (this use case’s starting point) will be the home view of the CoffeeBoy UI.

The use case

  • The use case starts on the Single Cup Of Coffee Order view.
  • Bob has the option to
    • navigate the list of coffee recipes.
    • go to the On-The-Fly Coffee Recipe view.
  • He navigates the list of coffee recipes.
  • He chooses a coffee recipe.
  • He has the option to
    • cancel his coffee recipe choice and again navigate the list of coffee recipes in order to choose an other one.
    • start the brewing process.
    • go to the Coffee Recipe view.
  • He starts the brewing process.
  • The Brewing Process view gets shown.
  • The brewing process progress gets shown.
  • He has the option to
    • cancel the brewing process.
    • wait until the brewing process has ended.
  • If he would decide to cancel the brewing process then
    • the brewing process would get paused.
    • he would get asked if he wants to cancel or continue the brewing process.
    • If he would decide to cancel the brewing process then
      • the brewing process would get canceled.
      • a temporary feedback would get shown.
      • the Single Cup Of Coffee Order view would get shown.
    • If he would decide to continue the brewing process then
      • the brewing process would get continued.
      • the brewing process progress would get shown.
  • He waits until the brewing process has ended.
  • A temporary feedback gets shown.
  • The Single Cup Of Coffee Order view gets shown.

Interaction flow chart ‘order a single cup of coffee’

Use Case #01: Order A Single Cup Of Coffee

Interaction flow chart ‘brewing process’

Brewing Process

Up next

In the next post we’ll design the order a single cup of coffee with on-the-fly recipe creation use case. Stay tuned!