asleep at the switch
asleep at the switch {adj. phr.}
1. Asleep when it is one's duty to move a railroad switch for cars to go on the right track.
The new man was asleep at the switch and the two trains crashed.
2. {informal}
Failing to act promptly as expected, not alert to an opportunity.
When the ducks flew over, the boy was asleep at the switch and missed his shot.
Categories:
Source: A Dictionary of American Idioms
