A knowledge base is a living organism. Every time you stumble upon an old note, you should consider it as a draft that needs improvements. Each time you go back to a note, you have the opportunity to expand it, correct it, add links, remove obsolete parts, etc.
Considering a note is final is detrimental to your learning, as it means considering that you have reached the definitive truth about something. Perfection. But perfection is an illusion. We can only tend towards it. Moreover, everything changes. What was true yesterday might not be tomorrow. For instance, what we consider the future of AI will surely be different in ten years. We keep learning and changing. When we come back to past notes, our point of view, knowledge, and state of mind might all be different, leading to new insights.
My advice is to approach note-taking as an iterative and incremental activity. Keep iterating and improving your notes. Incrementally, you’ll build a truly great knowledge base. Focus on keeping a continuous improvement mindset.