The degree of integration coupling defines how closely the systems (and their components) are interwoven within an application landscape. Modern software systems aim for modules that are as loosely coupled as possible. The components are interconnected in such a way that they exchange information with other modules via a manageable number of interfaces or are linked to a few components.
Loose coupling provides flexibility and improves maintainability.
The various components do not always necessarily communicate across system boundaries. Mostly they are located within the software system.
Loose coupling or decoupling ensures that changes to one module only trigger changes to another module if those changes affect the interface. Loose coupling’s high degree of flexibility provides significant value in the maintainability of IT architectures.