Very simple, 8 point answer:
- Bottom line results.
- Senior management is involved.
- A disciplined approach is used (DMAIC)*.
- Short project completion time.
- Clearly defined measures of success.
- Infrastructure of trained individuals (black belts, green belts).
- Customers and processes are the focus.
- A sound statistical approach is used.
By the way, Six Sigma activity is featured by projects, a lots of projects;the goal of each project is ‘improve one process at a time’
*(DMAIC)-Define, Measure, Analyze, Improve & Control