Determining Atomicity
There is a very simple test - can a subset of the requirement be implemented? Phrases like ‘the user will be able to X and Y‘ are tell-tale signs that a requirement is probably not atomic.
Why Atomicity Matters
Atomicity matters when developing a product roadmap. We can’t prioritize half a requirement for one release and the other half for another. Each requirement should be scheduled for a single release.
Testing of requirements should result in either a “pass” or a “fail.” A requirement should not partially pass its verification test.
Tracability of requirements is also simplified when each requirement is unique.
http://tynerblain.com/blog/2006/06/14/writing-atomic-requirements/
