The benefits of developing software with usability in mind are undeniable. The cost reductions of future revisions are up to 100 times less expensive, training can be reduced by a magnitude of 40, development cycle is reduced by up to 40%, and users’ productivity is increased by up to 200%.
This infographic by WitFlow gives an introduction on usability in the context of software development. Bugs in software will be inevitable and more plentiful compared to websites. Many of these issues can be solved in the early stages of development. Scrapping early designs and fixing bugs early can cost a fraction of the cost compared to releasing new revisions.
A key point in software usability testing is that it is an iterative process. You begin with testing, then move into analysis, then design, and finally coding. After coding is complete, you cycle back to testing to make sure everything is functional, and so on.