is an excellent book by
Jerry Weinberg (isbn 0-932633-32-3). As usual I'm going to quote from a few pages:
Organization inhibits reorganization (Minot's Law).
Growth is always non-linear.
Stability is the ability to ward off change.
A measurement system helps makes the software product visible.
Things will only get less visible over time.
Measure process not individuals.
Never use loops in a process description.
You need stability in order to make improvements.
Testing to improve, not to prove.
Without constant tending any process will deteriorate.
In a feedback control system it's only our perception that determines which is controller and which is controllee.