You put the thing in a drawer and it ceases to exist. A friend drops off your radar for two months, not because you stopped caring but because they were not in front of you. A task moves one screen away and it is gone. People with ADHD only half-jokingly call this object permanence, and while it is not the textbook meaning, it describes something very real: if you cannot see it, your brain files it under "does not exist right now."
Why this wrecks a normal to-do list
A standard list assumes you will come back and look at it. But if out of sight is out of mind, then a list you have to remember to open is a list that stops existing the moment you close it. You do not forget to do the task so much as forget the task was ever there. Adding more lists does not fix this. It just creates more places for things to disappear.
The same thing happens with follow-ups. A thread you are waiting to hear back on has no visual presence, so it silently drops until the other person nudges you and you realize weeks have passed.
Build a system that reaches out to you
The fix is not better memory, it is a system that surfaces things at the right time instead of waiting to be checked. Capture the moment a thing appears, before it slips. Attach enough context that future-you, who will have forgotten everything, can pick it up cold. And set a quiet resurfacing time so the item comes back to the top of your day on its own rather than living somewhere you have to remember to look.
When the system does the surfacing, object permanence stops being your job. You are allowed to forget, on purpose, because you trust the thing will come back.
That loop is the whole idea behind ADHD Notes: capture fast, keep the context, and let it bring the right thing back when it is time. See how it works.