Summarizing an article means compressing information. If I am able to reduce an article to a summary, annotated and I can efficiently remember what’s in it, I should be able to read my summary and throw away the source. But besides filler words or elaborated ways of conveys meaning, when I am summarizing I am interpreting that content. So I need an intention. I should have clarified the reason why I am reading that source and what I want to do with the knowledge I can extract from it. So a summary can never be universal, each reader will do their own version of their summary and their notes. That’s also why the value of personal notes is limited unless you are annotating for specific public and you are curating the readability and the consistency of your notes.