Open loops are tasks that need doing but have no deadline, plan or decision in place. They can be professional or personal (a unpleasant task from your manager, an awk- ward conversation you need to have with a friend). They are unresolved, open-ended issues that drain your energy, cause anxiety and ultimately detract from your produc- tivity. Close these open loops by writing them all down, and putting a plan in place.
Source: learn.filtered.com