What is the role of additional levels of abstraction in the architecture of software systems?

Additional levels of abstraction in software system architecture serve to simplify complex processes and increase modularity. They allow hiding implementation details, providing more understandable and manageable interfaces. This facilitates maintenance, extension, and testing of the system, as well as promotes component reuse. For example, an abstraction layer between the database and business logic allows changing the DBMS without altering the core application logic.