Software ergonomics and usability design
"Usability Design" is the current end of a development which came to the fore of information technology in the 80ies. While the above two terms are difficult to understand for outsiders, the term of "fitness for purpose" proves to be much more helpful, also because this term permits the determination of concrete, testable features.
From the beginning on dedicated to the users
Usability design is supposed to guarantee that the user-friendliness of software is taken into consideration from the beginning on and is preserved throughout the whole life cycle.