One of the most important characteristics of services is the participation of the customer in the service delivery process. A customer has the opportunity to get the services modified according to specific requirement.
Each of these characteristics is retractable per se and their inevitable coincidence complicates the consistent service conception and make service delivery a challenge in each and every case. Proper service marketing requires creative visualization to effectively evoke a concrete image in the service consumer's mind. From the service consumer's point of view, these characteristics make it difficult, or even impossible, to evaluate or compare services prior to experiencing the service delivery.