Several psychologists working in the field of emotions share the opinion that surprise is elicited by the novelty or unexpectedness of events. Thus factors determining the formation of expectancies become relevant for an appropriate analysis of surprise elicitation. In the present article it is reasoned that expectancy formation is determined, besides the probability of an incident, also by its desirability and importance. For achievement situations, such as in professional life, this means that desired outcomes (i.e. successes) being personally important for an actor should be higher expected than undesired (i.e. failures) and unimportant outcomes. According to this reasoning an important failure should contain the highest expectancy-disconfirmation and hence should result in the highest surprise. The present approach has been confirmed by empirical findings.