On researching taking notes, speciffically the Zekkelkasten method, I learned The Collector’s Fallacy.
In its essenses:
By taking notes, or making a Zettel, to summarize again what you understood, you then actually can reaffirm the newly acquired knowledge.
The gist here is to make notes as soon as possible. The article suggested a cycle:
One key is that the taken note should contain enough information that the original copy is no longer mandatory.
This post is itself a zettel.