misfire

noun

1. An act of misfiring.
2. (figuratively)A failure.

   “The fact is, Mr Carrados, Gertrude is a misfire. It was the surprise of her life (if I said "disappointment" you'd think me catty) when Mark married me, and she didn't set out to be pleasant to the interloper.”

   “Amazon’s misfires with Alexa may have led Google astray, said a former manager who worked on Google Assistant.”

verb

1. To fail to discharge properly.
2. To fail to ignite in the proper sequence.
3. To initiate an action potential without the proper stimulus.
4. (broadly)To fail to achieve the anticipated result.

   “His practical joke misfired and he nearly burnt my left hand.”