Conclusiones e implicaciones educativas

Jordan (1999a) offers a basic concept for a hierarchy of user needs (Figure 2.5). The foundation of the hierarchy represents products' basic technical functionality. If the customer considers his or her needs at this level as satisfied, the next demand will be related to usability (ease and efficiency of use). For example, for a washing machine this would mean that, at the point where the customer thinks that the machine washes clothes as cleanly, quickly, silently, etc. as expected, the customer will request more and,

according to the model, that would be that the machine is easy to use, e.g. that it is easy to load and unload clothes and to operate the control panel. The point is that the customer will want more once a lower step is satisfied. This implies that, when the machine

washes well and is easy to use, the customer will expect something more since good functionality and usability may not be enough to satisfy, or that, from a company

perspective, there are additional ways to create competitive advantages. According to the model, when the customer wants more, this will be related to affection and emotions of pleasure, such as joy of use and ownership. It also means that pleasure without usability, i.e. fulfilling the needs of the upper but not of the intermediate level, is not likely to satisfy the customer genuinely, especially over time.

Norman (2002) argues that, in order to be truly beautiful, wondrous and pleasurable, a product has to fulfil a useful function, work well, and be usable and understandable. An object that is genuinely beautiful is no better than one that is only pretty if they both lack usability. The design challenge is to make usability and beauty go hand in hand.

Cayol and Bonhoure (2004) believe that, as design is recognised as a key

becomes an important knowledge provider about users. Jordan (2000) argues that ergonomics in product design needs to more fully take the human being into account by incorporating the consideration of emotional based human factors in addition to the more traditional physical and cognitive aspects. This can be seen as industrial design and ergonomics closing up as knowledge areas; something not too strange since both areas consider human-product interactions (Green, 2002).

Figure 2.5. Hierarchy of user needs (Jordan, 1999a).

As the model indicates, in order to offer genuine customer satisfaction, usability must not be left out of the business of design since usability is a prerequisite for forming the kind of customer satisfaction that comes above usability on the hierarchy of user needs

(Figure 2.5), i.e. aspects relating to affection and emotions, such as pleasure of using and living with the product (see (Jordan, 1999a; Jordan, 2000) for more information of the four types of pleasure noted in Figure 2.5). This indicates that users must at least

consider the product's usability as acceptable to be able to appreciate the upper regions of the hierarchy of user needs. Taylor et al. (1999) remark that the three qualities,

functionality, usability and pleasure, interact and are not entirely separable but may be regarded as distinguishable, thereby providing a basis for further understanding,

discussion and investigation. Not surprisingly, factors related to pleasure are difficult to isolate since they are clearly affected by functionality and usability (Taylor et al., 1999). When the hierarchy of user needs was developed, an analogy was drawn with Maslow's 'hierarchy of human needs', establishing an order of physiological needs, safety needs, belongingness and love needs, esteem needs and self actualisation needs (Maslow, 1970; Jordan, 1999a).

FUNCTIONALITY

basic, technical functionality

USABILITY

ease and efficiency of use

PLEASURE

joy in use and ownership Physio-pleasure

Socio-pleasure Psycho-pleasure Ideo-pleasure

When considering ergonomics in product design, the influence of time aspects needs to be considered. In an analogy of physical ergonomics, where the likelihood of getting a permanent injury from performing a particular task is related to frequency and duration, time also influences emotional aspects. Aboulafia and Bannon (2004) distinguish between three feelings related to the time the customer interacts with a product.

1. Affection (short-time). This is the immediate response to a design, and is therefore especially important at the purchasing situation.

2. Emotion (medium time). This is a feeling that lasts several days.

3. Sentiment (long time). This is experienced on a longer term (months/years). Aboulafia and Bannon (2004) comment that predicting and designing for affection is likely to be the easiest of the three kinds of feelings. For example, by making the product provide a variety of sudden and unexpected changes, affectionate reactions can be

evoked in the user that may cause excitement or joy. Affection is indeed influential, e.g. in a purchase situation, but if this would be the sole focal point related to feelings in product design this may be superficial and leave the customer dissatisfied in the longer run, possibly leading to decreased company/brand/product loyalty. A difficulty is however that emotions are harder to predict since they do not depend on the immediate perceptual situation, and may require the entire setting to be designed rather than just the product.

To support the holistic approach described in this section it is important that the hierarchy of user needs and the time aspects of feelings are considered in the design process from the very start. This means that functionality, usability and pleasure are to be taken into account when setting visions for a product development project, when

assessing customer needs, when creating the product design specification, and then, through all stages and loops of the core design process (Figure 2.3). Issues of supporting designers to maintain a holistic approach towards user requirements are returned to in Section 3.2 and Section 5.3.