Users and Tasks
One of the most important prerequisites for usability is to:
“know your users and to understand their needs and requirements”
Successful development and purchase demands that we understand how and why people will use the product, what the most important features for users are, which functions are most central and how they should be structured to support the task.
Do not confuse usability with 'functionality'. This is concerned with the functions and features of the product and has no bearing on whether users are able to use them or not. Greater functionality does not imply improved usability!
A successful product or system requires a proper understanding of both user and organisational requirements. In contrast poorly specified user requirements in any context are one of the most significant factors behind IT project failure.
Breaking the usability definition down, we know that Effectiveness is about whether users can achieve what they need to do when using the product; Efficiency is about how much effort (e.g. time) it requires and Satisfaction is about how they feel about their experience using the product.
To make any sense of these three parameters it is essential to specify the context of use, namely:
- The users - who is using the product, for example are they experienced users, or novices?
- Their goals and tasks - what are the users trying to accomplish with the product?
- The usage situation - in organisational, technical and environmental terms where and how is the product being used?
