It happens.

When his 38-caliber revolver failed to fire at his intended victim
during a holdup in Long Beach, California, would be robber James Elliot
did something that can only inspire wonder. He peered down the barrel
and tried the trigger again. This time it worked.....
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The chef at a hotel in Switzerland lost a finger in a meat cutting
machine and, after a little hopping around, submitted a claim to his
insurance company. The company, suspecting negligence, sent out one of
its men to have a look for himself. He tried the machine and lost a
finger. The chef's claim was approved.
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A man who shovelled snow for an hour to clear a space for his car
during a blizzard in Chicago returned with his vehicle to find a woman
had taken the space. Understandably, he shot her.
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After stopping for drinks at an illegal bar, a Zimbabwean bus driver
found that the 20 mental patients he was supposed to be transporting
from Harare to Bulaweyo had escaped. Not wanting to admit his
incompetence, the driver went to a nearby bus stop and offered everyone
waiting there a free ride. He then delivered the passengers to the
mental hospital, telling the staff that the patients were very excitable
and prone to bizarre fantasies. The deception wasn't discovered for 3 days.
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A man walked into a Louisiana Circle-K, put a $20 bill on the
counter, and asked for change. When the clerk opened the cash drawer,
the man pulled a gun and asked for all the cash in the register, which
the clerk promptly provided. The man took the cash from the clerk and
fled, leaving the $20 bill on the counter. The total amount of cash he
got from the drawer...$15.
(If someone points a gun at you and gives you money, is a crime committed?)
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A thief burst into a Florida bank one day wearing a ski mask and
carrying a gun. Aiming his gun at the guard, the thief yelled, "FREEZE,
MOTHER-STICKERS, THIS IS A ****-UP!" For a moment, everyone was silent.
Then the snickers started. The security guard completely lost it and
doubled over laughing. It probably saved his life, because he'd been
about to draw his gun. He couldn't have drawn and fired before the thief
got him. The thief ran away and is still at large. In memory of the event, the banker later put a plaque on the wall engraved with the
words, "Freeze, mother-stickers, this is a ****-up!"
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Seems an Arkansas guy wanted some beer pretty badly. He decided that
he'd just throw a cinderblock through a liquor store window, grab some
booze, and run. So he lifted the cinderblock and heaved it over his head
at the window. The cinderblock bounced back and hit the would-be thief
on the head, knocking him unconscious. The liquor store window was made
of Plexiglas. The whole event was caught on videotape.
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As a female shopper exited a New York convenience store, a man
grabbed her purse and ran. The clerk called 911 immediately, and the
woman was able to give them a detailed description of the snatcher.
Within minutes, the police apprehended the snatcher. They put him in the
car and drove back to the store. The thief was then taken out of the car
and told to stand there for a positive ID. To which he replied, "Yes,
officer, that's her. That's the lady I stole the purse from."
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The Ann Arbor News crime column reported that a man walked into a
Burger King in Ypsilanti, Michigan, at 5 a.m., flashed a gun, and
demanded cash. The clerk turned him down because he said he couldn't
open the cash register without a food order. When the man ordered onion
rings, the clerk said they weren't available for breakfast. The man,
frustrated, walked away.
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Kentucky: Two men tried to pull the front off a cash machine by
running a chain from the machine to the bumper of their pickup truck.
Instead of pulling the front panel off the machine, though, they pulled
the bumper off their truck. Scared, they left the scene and drove home.
With the chain still attached to the machine. With their bumper still
attached to the chain. With their vehicle's license plate still attached
to the bumper. They were quickly arrested.
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When a man attempted to siphon gasoline from a motor home parked on
a Seattle street, he got much more than he bargained for. Police arrived
at the scene to find a very sick man curled up next to a motor home near
spilled sewage. A police spokesman said that the man admitted to trying
to steal gasoline and plugged his siphon hose into the motor home's
sewage tank by mistake. The owner of the vehicle declined to press
charges, saying that it was the best laugh he'd ever had.