Driving into deep flood water is the latest example of foolish motorists putting their cover at risk. We look at the silliest reasons for claims to be turned down.
The recent storms and flooding experienced by many parts of the UK has understandably led to a big rise in motor and home insurance claims.
But the bad weather has also given some hapless Brits the opportunity to demonstrate how quickly common sense can fly out the window in difficult circumstances.
Drivers ignoring flood warnings
The AA has reported that it attended more than 1,000 flood-related emergencies over the festive season.
A large number of these call-outs were the result of impatient motorists ignoring temporary "road closed" signs and driving into standing water.
It is estimated that more than two-thirds of vehicles which are stranded in flood water end up having to be written off.
But if a car insurance provider finds a driver has been negligent it could well reject any claim for repair or replacement.
Negligence could include drivers ignoring warning signs, or driving into water which is clearly more than a couple of inches deep.
Simon Douglas, director of AA Insurance, says: "All insurers will assess each claim on its merits.
"But if a driver is found to have been grossly negligent, and has ignored a 'road closed' sign for example, this could be grounds for having the claim turned down."
The AA said that a driver of a three-day old Mini drove his new car into three feet of flood water and ended up having it written off.
He told patrolmen he hadn't realised it would be a problem.
'Not easy to judge'
Steve Foulsham from the British Insurance Brokers' Association says: "Clearly if there were well publicised signs saying 'danger: deep water' then we agree that this might count in insurers favour.
"Otherwise we feel it is unreasonable for insurers to reject claims as motor vehicles generally are expected to be able to withstand adverse weather conditions in the course of normal use."
"It is not easy for motorists to gauge the depth of water when they are travelling along roads, and often only realise that the water is too deep when it is too late," he says.
"Motorists would drive through fords as a matter of course and you would not expect insurers to reject any claim resulting from that."
Car 'frosting' theft
Mild weather so far this winter means that "frosting" has not yet been a big problem.
This is where drivers leave engines running to defrost their vehicles in the morning, giving opportunist thieves the opportunity to drive off.
But there have been numerous cases of this happening during previous cold spells.
Douglas explains: "Leaving a car unattended with the keys in it is a big no-no.
"Some insurers won't pay out on a theft claim if the customer does not still have the keys."
Sat nav motorist almost drives off a cliff
The rise in the use of sat navs has also created new problems.
A number of drivers have recently been reported to have blindly followed their sat navs into rivers and, in the case of one motorist in the Pennines, almost off the side of a 100ft cliff.
"Again, the insurer's response will depend on the exact circumstances," Douglas says.
"But if you end up in trouble after following sat nav directions down a train track or into a river, the insurer could argue this is more than just bad luck and you have been negligent."
Read: Are sat navs a driving distraction?
Car insurance fraud versus forgetfulness
Failing to come clean when applying for car insurance can also have expensive consequences.
An insurer can turn down a claim if it finds a customer has omitted or withheld important information, such as speeding convictions or previous accidents.
But a distinction should be drawn between forgetfulness and deliberate insurance fraud, says Douglas.
"I have come across one case where a 50-year-old customer in Cornwall actually turned out to be a 20-year-old living in London.
"But this kind of thing will be treated differently to someone who forgets to mention a speeding fine, for example."
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