As Benjamin Franklin said, "We are all born ignorant, but one must work hard to remain stupid."
And by this measure, many of our colleagues are apparently working very hard indeed. We've all known them: the co-workers that are so dumb that they don't even realise their ignorance.
In 2004, a survey by the Learning and Skills Council (LSC) indicated that more than one in ten Brits were incompetent at their jobs. (The people that carried out the survey haven't quite managed to repeat their performance since, so we don't have any more up to date figures.)
Sometimes, a colleague's stupidity is simply entertaining; less so if their incompetence makes it harder for you to do your own job.
But what's the best way to deal with an incompetent colleague? For a start, say experts, you shouldn't assume that they really are as clueless as they seem.
"Sometimes the problem is that she is really smart and skilled, but just not suited for the current role. Maybe he lacks the appropriate training and needs time to learn and grow. Or this employee has a personality that clashes with your team," says Robert Half of jobs website Careerbuilder.
In any case, general stupidity really isn't your problem, unless it's affecting your team's work. If it is, a bit more training might help.
And if all else fails, you could let off steam by heading over to a new discussion thread on Reddit, where frustrated staff are sharing their stories.
Lack of the basics
"Heard over the pod divider: 'A-B-C-D-E-F-G-H... A-B-C-D...' It turned out that she was filing and the only way that she could remember the alphabet was to sing the song, again and again and again and again..."
"My co worker, she asks me to re-fax the sheets. So I ask her, oh is it blurry or something? Maybe I can fix the fax machine. To which she says 'No, everything's great, it's clear and all - it just came out upside down.'"
"Co-worker didn't understand why you would still have the original when you fax a copy to someone. He actually thought the physical paper would get transported."
"I accidentally emailed you a confidential document. Could you email it back to me?"
"She asked whether China is in 'America or Canada?' I literally had to explain Asia's existence to her."
"She thought you could walk to the US from the UK because the sea 'isn't that deep'."
"I come from Newcastle upon Tyne but was working in Bradford. A girl on my team from Bradford asked me 'What currency do they have in Newcastle?'."
"One of my colleagues asked where Portuguese people are from. I looked incredulously at her and said 'where do you think?' And she replied 'Africa?'. After most of the office suppressed a giggle I told her it was in fact Portugal. She replied, 'It can't be Portugal, that's the capital of Spain!'"
"You know Albania, yeah? Is that where albinos come from? The ones with the white hair and red eyes?"
"UK office. Late warm May. First day at work after a holiday. Colleague asks where did I go. 'Amsterdam'. She responds with 'Mmm.. snowboarding again?'"
"We were decorating for a party, blowing up balloons with our mouths. After a few she said, 'Why aren't these floating? Did I buy the wrong kind?'"
"A co-worker was telling a story about him talking to someone from New Zealand, and our receptionist asks, 'Oh? What language do they speak?' My buddy says, 'English. New Zealand is like Australia, but with more sheep.' Receptionist says, 'Ha! I bet they wear a lot of cotton then.' And she follows that up with, 'I think it's sad that they have to kill all those sheep just to make sweaters.' Apparently she thinks sheep are stuffed with cotton."
"I worked with a woman who thought that the windfarms in southern California were actually huge fans used to combat global warming by blowing cool air into the desert."
"I asked a co-worker if her ancestors were from a certain country, she didn't know what that word meant. So after I explained it to her, she says 'I don't believe in that, I came from my mom and she came from her mom. That's it.'"
"When he was trying to argue that the moon landing was faked he said 'I've watched the videos. How can there be shadows on the moon? There's no gravity!'"
"I once had someone tell me she was going to fire me and hire someone else. I own the company... and fired her. It turns out she was telling other people she owned the company as well, instead of just being the office manager. Then I learned she stole a lot of money. I called the police, and her trial is in a couple of months."
"New co-worker comes in with a master's degree at the age of 22 in a high paid position... and spouts off about how nice her credit card is because no matter how high her balance gets her monthly payment never changes, it's always $25 a month. I ask her if she has always just been paying $25 a month. She says yes. I ask her what happens when it maxes out, she says she just sent the bank a copy of her salary contract and they raised the limit again."
"Considering how much water you need to clean a coffee pot 'it is cheaper to buy a new one'."
"This girl asked what the qualifications for being a president were. Someone replied that you have to be a natural born citizen. She turned around and said 'you mean just because my son was born by C-section he can't be president?'!"