Consequences of bad user interfaces
 

Bad interfaces may cause users to

• need more time for performing their tasks
• make more errors
feel dissatisfied
• need more time for learning how to use the software
not learn/use the full functionality of the software
The linked image shows the main display of a reservation system in a restaurant. The headwaitor does not use the functionality of the software since it is too cumbersome. Instead he writes on the screen with a felt-tip pen.
(if given a choice:) refrain from using the software


Good interface design therefore is important for any kind of interactive software, and of utmost importance in

• systems with high costs of failure (e.g., nuclear power plants, space mission control)
• systems with high demands on operators (e.g., rescue coordination centers, combat aircraft, call centers)