good software architecture allows decisions about frameworks, databases, web servers, and other environmental issues and tools to be deferred and delayed. Frameworks are options to be left open. A good architecture makes it unnecessary to decide on Rails, or Spring, or Hibernate, or Tomcat, or MySQL, until much later in the project. A good architecture makes it easy to change your mind about those decisions, too. A good architecture emphasizes the use cases and decouples them from peripheral concerns.
