The system development process is
nIterative and
incremental
uInadequacies often
are found.
uTesting uncovers design and implementation flaws.
uTest plans must be
updated continually as the process
proceeds.
nCompositional
uThe system is
composed of simpler pieces (objects,
algorithms).
nEvolving
uThe problem a system is designed to solve inevitably changes over time, requiring system maintenance.