Why understand the actual use of your system?
Build up and observe in situ a panel of representative users

This experimental approach allows you to focus your development on your target, i.e. the user of the product or service. Although iterations may seem like a substantial investment, they have been shown to cut the number of prototypes by half, the number of man-months by a quarter in the design phase and by a third in the optimization phase.

We need to remind you of a few definitions:

Acceptability is the appropriation of the object by its user.

Acceptability = Usefulness + Practicality + Price acceptability

Utility is the way in which the system will perform the required functions.

Usability is the "degree to which a product can be used, by identified users, to achieve defined goals with effectiveness, efficiency and satisfaction" (ISO 9241).

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