I understand the grammar point "Verb (Dictionary Form) + ことはない" can mean either "There is no need" or "There is no possibility" depending on context.
However, what are the differences? Are there any nuances which I should be aware of? Can they simply be interchanged in any circumstance?
"There is no need" example:
わざわざここに来る必要はない
vs
わざわざここに来ることはない
"There is no possibility" example:
今日の会議を忘れる可能性はない
vs
今日の会議を忘れることはない