Use when someone unintentionally reveals information they meant to keep secret.

Accidental Revelation

It often implies the speaker immediately regrets the slip or tries to correct it.

Subtle Nuance

Sometimes used when the speaker doesn't immediately realize they've given away a secret.

Use when someone fails to take advantage of a situation that was in their favor.

This meaning often implies there was a limited window of opportunity that wasn't seized.

Implies a sense of regret for not acting quicker or being more alert to an opportunity.