Section 1
Methods and Models for Usability and UX
1 Usability and User ExperienceMethods and Models
Marcelo M. Soares, Tareq Ahram and Christianne FalcĂŁo
DOI: 10.1201/9780429343490-2
Contents
1.1 Introduction
1.2 What Is Usability
1.3 Focusing on the User
1.4 Understanding Consumer Products
1.5 Context of Use for Consumer Products
1.6 Usability Measurement
1.7 Usability Models
1.8 Conclusion
References
1.1 Introduction
In the home, office and leisure environments, we deal with a wide variety of consumer products on a daily basis. To gain a cutting edge in an increasingly competitive market space, manufacturers are constantly looking for ways to improve the quality of their products. On the other hand, users are increasingly demanding of better quality products and have less tolerance for difficulties in the use of products, giving greater emphasis to designs and products that are easy to use and allow for ease of learning and better aesthetics (Han et al., 2001). If a product or system is difficult to use, it wastes user time and causes frustration and discomfort, thereby discouraging its use.
The market for consumer products is characterized by constant change. It is expected to add new features and functionality to products, making them increasingly complex over the years. Manufacturing companies are expected to keep up with this rapid technological evolution, designing and manufacturing products not only with better performance but also lower costs at an accelerated pace. According to Acosta et al. (2011), companies identify usability as a strategic factor in product competitiveness, efficiency, differentiation and best practice, which can be integrated into the different phases of the product development lifecycle. Product development, according to Krishnan and Ulrich (2001), is the transformation of the market opportunity into a product available for sale to consumers and users.
Based on the belief that the design of the product must meet the userâs needs, usability focuses on creating an excellent user experience, which is in the process that underlies the real goal of usability. The user experience and usability evaluation process starts by looking at who uses the product, understanding their goals and needs and selecting the right techniques to answer the question: does this product meet the userâs needs and requirements?
Usability evaluation focuses on understanding how people use the product, with regard to the interaction between the user, the task and the product. Some authors (Jordan, 1998; Norman, 2006; Preece et al., 2002; Göbel, 2011) report that in the past, many products were designed with little emphasis on the user, and this caused frustration and wasted time as they did not offer adequate usability. With the saturation of the market and consistent technological advancements, aspects such as aesthetics and features that can be associated with usability have become ever more important for determining product value and brand success. In parallel, this issue was emphasized by the growing complexity of products, requiring greater attention to user needs, and in order to allow technical benefits to be explored. During this phase of identifying user needs and requirements, which started in the 1990s, usability parameters received greater attention, initially with a focus on market studies, engaging the user more and more in the design process.
Although usability is well known as a key element in product design, the concepts used are derived from the field of humanâcomputer interaction (HCI), highlighting the need to formalize the concept when it comes to consumer products. This chapter introduces various usability concepts, presenting the evolution of their application in consumer products over the past three decades.
1.2 What Is Usability
The concept of usability was first discussed by Shackel (1984), who defines usability of a system or equipment as its ability to be used easily and effectively, in human functional terms, by a specific range of users, when receiving adequate training and support for fulfilling a specific task, within a certain expected time interval and environmental factors. That is, usability corresponds to the capacity of product, system or service to be used easily and effectively by humans (Shackel, 1991, p. 24).
Usability is better known and better defined in terms of the approach to HCI. These concepts are used to improve the userâsoftware interface side of the product (Nielsen, 1993). The importance of this dimension in the design of consumer products was first considered in the early 1990s by companies such as Thomson Consumer Electronics, Apple Computers and Northern Telecom (March, 1994). Later, Jordan (1998, 2000) noted a theme of growth with the increase of publications in the field, more usability professionals being employed, more research conferences on the subject and greater public awareness of the field of usability and user experience. Since the last decade, usability has been applied on a large scale to design products that are easy to use, easy to learn, accessible and comfortable, making our daily life less stressful and more productive.
Nielsen (1993) considers usability as an aspect, among others, that influences the acceptance of a product, whose objective is to develop transparent interfaces capable of offering easy, pleasant, effective and efficient interaction, allowing the user full control of the environment without becoming an obstacle during the interaction.
Nielsen also suggests that usability and ease of use can together form a usable system. The usefulness of the product can be defined as its ability to perform its intended functions and necessary operations, and that usability corresponds to how well the product works so the user can use its functionality. This view is supported by Eason (1984), stating that usability can limit the degree to which a user can perform a potential objective of a computer system.
Steve Krug, in his famous book Donât Make Me Think! (Krug, 2000), features usability from a simple perspective, with the certainty that something works well when a person with skill and average experience (or even minimal experience) can use a product for which it is intended and designed, without getting confused or frustrated. According to Bevan (1995), usability is often defined as the ease of use and acceptability of featur...