A status message confirms that the
target temperature has been changed.
The water heater has turned on to
heat the water to 129F.
Image 1:Figure 9.30: The Lowes Iris water heater UI, showing the status message
Here, the UI is showing the data as being in the process of being sent. In
essence, the system is saying to the user: ’thanks for your instruction, let me
see whether I can do that’. This requires the user to know a little more about
how the system works in order to understand why the instruction isn’t just
acted upon. It also introduces the possibility of failure to every interaction,
successful or not.