Libraries by definition have a narrower scope and hence are more easily adapted to new situations. Frameworks by their nature affect the whole codebase. This

Libraries by definition have a narrower scope and hence are more easily adapted to new situations. Frameworks by their nature affect the whole codebase. This is the low-coupling/high-cohesion benefit of libraries as seen in many places in software engineering. A codebase with low coupling is inherently more flexible and maintainable. Libraries and well defined, sensible interfaces are critical to good engineering.