The phrase originates from the use of flintlock muskets in the 17th and 18th centuries. When the gunpowder in the pan (a small container holding priming powder) ignited, it would create a flash, but if the main charge in the barrel didn't ignite, the gun wouldn't fire. This resulted in a fleeting flash but no real action.
- from dear Google with editing
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The idiom came in the English subtitle of a French movie, about the life of a razzle-dazzle fashion designer. I watched it on the plane.
It reminded me of a person I knew at my last company. He came from the same company I was in before, had a very good reputation there and was given a high pay here, of course.
But the strange things started not long after he joined: he openly mentioned his high salary number to a few coworkers, which is a big no-no in western culture. Then others said he seemed to be stoned sometimes, and was not doing much at work.
I was busy as a bee at work and tired as a dog at the end of each day, so paid minimal attention to the office rumours, other than occasionally passing by him dressed in colourful shirts, in the cafeteria at lunchtime.
One year later, bad news came: he was let go by the company. So from the top 10% of the high tech labour pool (per company HR hiring standard) to the bottom 10% in work performance (per company HR lay off standard), he was a "flash in the pan".
Poor guy.
