One of the consequences of interactivity is that the service provider and the customer must be frequently in the same place and at the same time, although the use of information technologies can reduce that need, at least with respect to information services . Other important repercussions of this feature of many services are
trade service will be a function not only of the activities of the borrower, but also of the own contributions of the clients; that the productivity calculated through the labor contributions of the supplier can be achieved at the cost of more work by the user, and that there is likely to be a lot of heterogeneity among the products offered by a service organization. Some services may be relatively normalized, but many others are customized or at least customized in series by assembling the service from multiple modules, which are coupled according to the needs of each client. Some other services are made completely tailored, specially adapted to the particular needs of a client. The manufacturing industry also varies, offering mass production, serial customization and specialized production in small batches (the rapid realization of prototypes is only characteristic of service companies that actually produce physical goods, although their objective is to prove the viability of the designs). The heterogeneity of the products increases the difficulty of evaluating the quality of the service prior to the production.