The article proposes a new taxonomy and managerial approach to competitive advantages. Two central suggestions are made. First, the list of competitive advantages understood as customer advantages and therefore: advantages carried out, i.e. observable value added for customers – should be extended to time-related differences. Second, implemented competitive advantages should to be regarded as evoked and ongoing expectations of fulfilled promises. Reliance understood as the fulfilment of promises consequently acts as a premise for the constitution of a competitive advantage and might even be regarded as an advantage itself. The paper provides empirical insights from a large sample study conducted in a B-to-B pre-purchase setting asking for decision criteria of organizational buyers. The results of this study indicate support for both suggestions.