Leave it in a better state than when you found it.
A good mantra but too nebulous to include in a Definition of Done.
An alternative with a more concrete scope:
Always leave it 1% better than when you found it.
Tiny, incremental steps forward taken regularly are:
- Easily achieved.
- Easily validated.
- Immediately impactful.
- Habit forming.
Spring cleaning is a project. Tidying as you go is a practice.