It is usually taken for granted that Direct Manipulation is the best interaction style for inexperienced or non-expert users; moreover, this style of interaction is generally considered the best for almost every situation and user. The recent shifts in technology that we all are currently experiencing have given rise to a great deal of new kinds of users performing specific tasks in a variety of scenarios. In this paper, we focus on users who access a system occasionally, infrequently, or in an unplanned way; i.e., users who do not want or cannot afford a learning curve. We show that for them, Direct Manipulation is not always the most suitable style of interaction. We assess the advantages of guiding this kind of users, in particular through the guided interaction frame- work known as Goal Driven Interaction. GDI can be viewed as a superset of wizards providing support far beyond a few steps through dialogs. Indeed, GDI is an interaction style with characteristics of its own. We report a complete user test that backs up previous hypotheses. The analysis of empirical data proves that GDI is more time-efficient than DM, requiring fewer moderator assistances for the users. Post-test questionnaires confirmed that participants had a strong preference for GDI.
