Change is the normal case in systems development. This adds to the character of data modeling as a brake. Enterprise data models create additional complexity in the process of software development. The application development is impaired by the urge to use top-down data modeling practices. Integration of systems can lead to the violation of normalization rules, such forcing the integrated systems to be adapted - valuable time elapses for formal matters.
Data modeling has to incorporate all possible future options of a systems.
This slows it down to inoperabilty. The level of abstraction is tending to become higher and higher until nobody is able to understand the results of the process. Buying prefabricated data models off the shelf is naive. Prefabricated data models are useless. Despite all criticism the following basic requirements are acknowledged as essentials of any process of software development.