C3W4 - Video on Fairness - Did not understand one part

Video on Fairness says at the end:
‘Finally, for predictions which don’t have a good margin of separation from their decision boundaries, you should consider reporting the rate at which the label is predicted.’
What rate is being referred to here? Does it mean % of inferences that don’t have good margin of separation from decision boundary? Or some other concept?
Please clarify.