flash in the pan

Cultural  

1. Someone or something that promises great success but soon fails: “The rock group that was all the rage last year turned out to be just another flash in the pan.”

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flash in the pan Idioms  

1. An effort or person that promises great success but fails. For example, His second novel proved to be a flash in the pan, or We had high hopes for the new director, but she was a flash in the pan. This metaphoric term alludes to the 17th-century flintlock musket, which could be fired only when the flash of the priming powder in the lockpan ignited the charge in the bore. When it failed to ignite, there was only a flash in the pan and the gun did not shoot.

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Example Sentences

Is Newsom the Democratic front-runner or a mere flash in the pan?

From Los Angeles Times

"We thought that tool use could have been a flash in the pan and then disappeared. When we see 300,000 years of the same thing, that's just not possible," he said.

From BBC

Was Aberdeen's brief revival flash in the pan?

From BBC

"But you also need to have the right team around you to make sure it's not a flash in the pan and you can grow it in a sustainable way."

From BBC

"You want this moment to not just be a flash in the pan, you want this to be the start of a legacy." she says.

From BBC