Most often, the reason something is "on your mind" is that you want it to be different than it currently is… — David Allen

Most often, the reason something is "on your mind" is that you want it to be different than it currently is, and yet:

• you haven't clarified exactly what the intended outcomes is;

• you haven't decided what the very next physical action step is;

• and/or you haven't put reminders of the outcome and the action required in a system you trust.

That's why it's on your mind.

Source: Wikiquote · CC BY-SA 4.0