The LEAN simple rules:
- Spend time only on what adds real customer value.
- When you have tough problems, increase feedback.
- Keep your options open as long as practical, but no longer.
- Deliver value to customers as soon as they ask for it.
- Let the people who add value use their full potential.
- Don't try to tack on quality after the fact – build it in.
- Beware of the temptation to optimize parts at the expense of the whole.
I love these rules. They apply to testing just as much as they apply to software development.