Scenario Based Product Design

Manufacturers of products are more and more confronted with complaints from customers that are not related to technical or functional failures, but to an unexpected mismatch between actual product use and intended use by the manufacturer. Improvement of user – product interaction, also referred to as usability or the ease of use of a product, is therefore an issue that gets more and more attention in product development. Good usability can lead to increased customer loyalty, a decrease of product returns and a decrease of call rates at customer service desks. However, usability is not a product quality that is intrinsic to only that product. It is a quality attribute of the interaction between a product and its user in a particular environment. Therefore usability not only depends on the product characteristics, but on use situation characteristics (user, goal, environment) as well.

An accurate, comprehensive insight into how a product is used in practice by its users is essential for designing products that meet user expectations. Obtaining insight in these use situations is however complicated, because the behaviour of users is never static or uniform and increasingly products have become adaptive, and thus exhibit unpredictable behaviour as well. Therefore in product development processes that take usability into account, there is a need for a frame of reference to these use situations. Scenarios can serve as such a frame of reference.

Scenario Based Product Design (SBPD) is a generic term for design approaches that apply scenarios in the design process with the aim of achieving a high quality of product interaction. We define scenarios as explicit descriptions of the hypothetical use of a product by a certain person under certain circumstances. Scenarios can be applied throughout the design process. In the analysis phase they can be used to gather and represent user needs and wishes, in the concept phase they can be used to create and reflect on concepts and in the prototyping phase they can be used as a frame of reference for user testing. In all phases they serve as a communication tool because they are very easy to understand (regardless background or training). For example in the analysis phase they can be used to have users confirm the current use situation and problem domain and in the concept phase they can be used to discuss concepts with users and other stake-holders. Instead of considering usability requirements with regard to users and environments independently, scenarios integrate reflection on these elements. A scenario-based approach has the advantage that a scenario can describe what happens in a particular situation without committing to details on precisely how things happen. Furthermore, a scenario can be made deliberately incomplete to help developers cope with uncertainty.

SBPD is not a single design method. Instead it is a category of numerous approaches that apply scenarios for different purposes, with different sources of inspiration and means of expression. Because each design problem is unique, each case needs a dedicated design approach which includes a structured application of scenarios throughout the design phases.