Writing "living" text is different than writing publish-once text.
- You can write for learning.
You take notes
- to extend your working memory
- to explain something to yourself
You can write responsively.
Think of Wikipedia. It changes whenever
- a notable event happens
- new information comes to light
- someone notices an inaccuracy
Writing living documents means that you don't have to be done in order to write something worthwhile. Evolve it as you see fit, or as you see the need!