Relief is a positive emotion experienced when something unpleasant, painful or distressing has not happened or has come to an end.
[4] In a 2017 study published in Psychology, relief is suggested to be an emotion that can reinforce anxiety through avoidance[5][6] or be an adaptive coping mechanism when stressed or frustrated.
Near-miss relief is the experience of narrowly avoiding something aversive, e.g. the cancellation of a test for which one forgot to prepare.
Task-completed relief is experienced upon finishing an aversive task, e.g. a complicated tax return.
It appears that near-miss relief triggers people to think more about the scenario for the future, maybe how to avoid something like it happening again.