Huge Systems – and why users perceive them as complicated
This is an extract from an internal TDC testing conference presentation in March 2007. It is based on Don Norman's article "Cognitive Engineering", 1986 and his book "The Design of Everyday Things", 1988.
No feedback from the system to the designer
- In any system there is feedback between the users and the system
- On the other hand there is no feedback from the system to the designer (for example the IT architect):
The users need:
- Feedback to tell the state of the system
- To experience a coherence between the state, the results, and the possible actions of the system
- To be informed about possible actions
In general the designer focuses at devices and architecture, while the users focus on tasks and processes.
The designer wants elegance
The designer always seems to aim for elegance in the internal design – expecting that the elegant and simple solution will be mirrored in the user interface.
But it is not necessarily so, at there need not be any connection between the user's understanding of the system through the user interface and the system's internal design.
If you need to explain – then improve the design!
When you are working for a good design, then:
- You need coherence between state of the system, results, and possible actions
- The users need influence on all steps in the development of the design – as it is a general rule that you need to redesign five times before the design cannot be improved
- The need for a user guide is a sign of bad design
Roughly speaking: If the users demand for explanations then improve the design!
Test as an early feedback in software development
In software testing there is a possibility to create some of the needed interaction:
- Testers are the first to know the new system image
- If the system is error-bound, then most of the errors are caused by bad design
- When testers find errors they may be able to make the designer change his design