The chronology is in a spreadsheet. The good paragraph is highlighted in a PDF nobody else has. The research answer was right in March and nobody has looked at it since. The note that mattered is in an email to yourself.
Every tool you use hands you a document that is finished the day it is made. Six months later the case has moved and none of it has.
And the part that matters most has no home at all. Your theory of the case, why that paragraph matters, which facts must land before the argument works — that lives in your head, in a legal pad, and in the memory of whoever was in the room. There is software for storing the file. There is none for thinking about it.