Roundabouts have increased in a significant way in recent years in Moroccan cities as they have been seen as a solution to congestion problems and traffic safety issues. However, roundabouts are relatively new to Moroccan drivers and the rules of priority to which the users are accustomed are reversed in roundabouts. This can lead to confusion and misleading. The overall objective of this study is to identify roundabout features that appear to play a role in the difficulties that drivers encounter when crossing roundabouts. This paper will present a comprehensive understanding of what is required of drivers when crossing roundabouts. We then predict failures that can occur at roundabout using our driver error taxonomy. A case study of two roundabouts in Morocco is analyzed as illustration. The paper concludes with implications of the findings to future design.