I wrote a paper on this topic for a course. Was a pretty interesting experience. Below is the executive summary. You can download the paper as a PDF as well.
Usability is an important quality attribute that has a great impact on the user experience of a software product. To the user, the interface is the product. Thus it is very important for software teams to ensure high levels of usability in their products for them to be accepted and liked by their end users.
There are a number of hindrances that prevent integration of usability tasks in the development lifecycle. The cultural gap between the fields of human computer interaction and software engineering is perhaps the underlying cause of many issues that arise when engineers are made to use usability techniques. Most teams are not aware the importance of usability, or are of the opinion that regular development staff can build perfectly usable interfaces. Management is sometimes of the view that usability tasks will be costly and time consuming. Education and training of engineers and management is required to overcome these issues, as well as customizing usability techniques so that they are cheap and lightweight, hence easy to adopt.
It is also important to define what the team understands by usability, since it encompasses a large amount of characteristics. Usability goals should be decided and usability characteristics of the system should be documented so that they are testable.
There are a wide variety of usability techniques and methods, each having its own strengths and weaknesses. It is important for teams to be able to make the decision as to which technique is required in a certain condition. This report looks at the different stages in the development lifecycle and which usability techniques are suitable therein. An overall approach to integrating usability techniques and practices into the different development stages of a typical iterative development lifecycle is presented. Planning activities and roles related to these techniques are also discussed. Usability integration with slightly different lifecycles, such as XP and ACDM are also examined.
For easier adoption of usability techniques at an organization level, it is important to introduce easy and cost effective techniques at the grass root level. This results in teams reaping the benefits of usability techniques without expending a lot of budgeted resources. In this regard, studies are looked at that highlight usability techniques that are widely used, cheap and easy.
Usability is an integral part of everything that is engineered, whether it be software or otherwise. With the increasing complexity of software systems, it is even more important to design interfaces that are easy to understand and use. Usability is also not something that can be slapped on at a certain point in time. Hence it is important to ensure that usability tasks are planned and carried out during all phases of the development lifecycle.