Everyone makes mistakes, it's part of being human. Although, let's be real, some mistakes are funnier than others. Especially when the person is completely wrong, and doesn't seem to realize it.
People on Reddit share the time when they thought someone was on another level of stupid. Content has been edited for clarity.
The Bus Driver Didn’t Prove Her Point

“Summer camp counselor made all the kids on a school bus keep the windows up on a hot day. Her reasoning was because ‘they could feel the air conditioning’ coming from the front of the bus.
It was so hot, and I (maybe 10-years-old at the time) had to explain to the 40-year-old counselor the ‘air conditioning’ they were feeling was the wind coming in through the bus drivers open window. She still didn’t believe me.
I begged her to ask the bus driver to confirm the bus did not have air conditioning, but she didn’t want to bother him while he was driving. It was like an hour bus trip.
She finally got hot enough and asked the bus driver if the bus had air conditioning.
He jokingly said, ‘The bus only has air conditioning when the windows are down and the wheels are turning.’
She then looked back at me and said, ‘See? I told you the bus had air conditioning.’
She proceeded to force us to keep the windows up.”
There’s A Difference Between The Two

“This was my first experience in retail where I learned what many customers would be like.
Seasons were changing, so we put a lot of shirts we had to get rid of in the front and made them 50% off. I was working the register when a woman came up to buy her things. I rang her up and could see a look on her face like something was wrong. That’s when the following happened.
Lady: ‘Why is this so much?’
Me: ‘Pardon me?’
Lady: ‘This should only be $10, not $20.’
I thought maybe her item was on sale, so I asked if she could point out the sign because I wasn’t aware of it. It was a small store and we didn’t have to walk anywhere.
Lady: ‘This sign here.’
Me: ‘This sign says that all shirts are 50% off.’
Lady: ‘Yes, so why is this full price?’
Me: ‘This is a hat.'”
A Simple Fix

“While driving from one big city to another, I stopped in a small town to eat at a fast-food chain in Texas.
I order my food, get my orange number tent, and sit down to wait for my order.
The lady who’s bringing out orders has this ‘I give up’ look on her face as she’s calling out numbers that guests aren’t claiming. Each time this happens, she speaks to a couple of tables to seemingly figure out who the food is for.
Then I hear her call for number 55 while holding a tray of food for one person. I was number 54 and noticed I was the only single-party guest there. We make eye contact and she heads towards me.
She confirms my order with me and says ‘Sorry, for some reason the computer prints one number higher.’
I immediately ask, ‘Well, then why don’t you just call out one number lower than what’s printed?’
She freezes, and I can see the gears turning in her head.
I tell her ‘Thank you,’ and she goes on her way.”
He Seemed To Forget An Important Detail

“My friend is allergic to walnuts. One day, he made this sandwich in our college dorm. It had walnuts garnished on top of the bread.
I then remember him telling me, ‘Oh look, there are walnuts on the bread,’ and proceeds to eat the entire sandwich (At the time I didn’t know he was allergic).
I leave to shower, and when I come back there are two paramedics in our dorm taking him out on a stretcher.
The following day, I asked what happened to which he replies something along the line, ‘I accidentally ate some walnuts which I’m allergic to. By the time I went to get a Benadryl, my throat had started to close and I couldn’t swallow it so I had to call 911.’
I was just utterly shocked by how he even let this entire situation happen. I really couldn’t believe it.”
That’s Not What It Means

“At the time, I was working at a grocery store that had a Coinstar machine. Basically, you could place all of your unwrapped change in it and it would be converted for a small fee you could use for actual cash. I was walking past and noticed a woman struggle with the machine.
I stopped to help her, and it turns out she had accidentally hit ‘Spanish’ as a language selection. I quickly explained what she needed to do, figuring she couldn’t read Spanish and this is where her struggles came from.
So I run through how it works and show her where the receipt will print out she can turn in at customer service for the cash.
She turns and looks at me and says, ‘But I don’t want Spanish money.’
Sigh, then I have to explain to her that she would get paid in US dollars.”
A Very Simple Soultion Here

“My wife’s cousin and her husband/not-baby-daddy-of her-unborn-child fell on self-induced hard times and needed a place to stay for a bit. We set up a queen-sized air mattress in the living room for them.
For three weeks, I woke up to go to work and every morning saw them sleeping on it sideways with their legs hanging off the edge. Then one day, she asked me to buy her a bigger air mattress because this one was hard on their backs. I told her to turn her body (the freaking thing even has a built-in pillow on one end).
Her response was that then they couldn’t see the TV.
Then freaking turn the air mattress to face the TV! That’s the story of how I became known as a rude guy to the trailer trash side of the family.”
This Woman Was Very Confused

“I locked my purse with my keys and cell phone in my apartment. I went to the office to ask maintenance to let me in. The woman at the desk said she would call maintenance, and asked for a phone number they could reach me at. I said there wasn’t one because my cell phone was locked in my apartment.
She insisted she needed a number. I said I could give her the number but that I wouldn’t be able to answer if they called. She suggested I get my phone out of my apartment so that I could answer when they called.
I rolled my eyes at her and said if I could get in my apartment to get my cell phone I wouldn’t need maintenance to let me in. She never did understand me. But maintenance did show up ten minutes later.”
She Wanted To Follow The Rules

“I’m fairly certain that people who have to work at front-of-house desks deal with so many stupid people that they start to lose their own sense of sanity. I once decided to go see my doctor about something and, as it happened, my bus home from work stopped right outside my doctor’s office.
So I decided to just walk in and see if I could make an appointment there and then, knowing full well that I might have to come back later. But the waiting room was empty. And I walked up to the woman at the desk, who asked if I had an appointment. I told her I didn’t and would like to make one. She told me that I’d have to call the number, and pointed to it on the digital signboard.
I asked if I can just make an appointment with her, and she again pointed out the number on the sign. I asked who I’ll be talking to when I call that number, and she said that she would answer the phone.
So I took my phone out of my pocket, looking her in the eye the whole time, called the number, the phone on her desk started ringing, she actually said ‘Excuse me one second!’
She answered the phone, and then I had a conversation with her. On the phone…while standing right in front of her.
I asked for an appointment. She asked when I wanted it. I said that right now would be good. She said OK, took my details, and hung up.
She then looked at me and said, ‘How can I help you?’
I told her that I have an appointment and she told me to have a seat. I went and sat down while she typed some info into her computer, and then the digital signboard popped my name up, and she spoke into her microphone to call my name, as I’m sitting there.
The only freaking person in the room.
When I went up to the desk she said, ‘Hello, sir. How can I help you?’
‘I have an appointment,’ I said in a defeated tone.
‘Name?”
I mean, are you serious?”
He Really Should Know What That Is

“I was helping a colleague with his graduate thesis film. My job was to animate a solar eclipse since we couldn’t shoot one for real.
I animated it using some real-life reference footage to make it look realistic. When I showed him, he asked why the moon was black and had no detail.
I asked him if he had ever seen a solar eclipse and he replied ‘Yes of course, but I want this one to look surreal since it’s the moon in front of the sun, it’s not like a normal solar eclipse.’
At this point, it became clear something was amiss; and after asking a few more clarifying questions it became clear he had no idea that the large object passing in front of the sun during a solar eclipse is, in fact, the moon. I confronted him about it and he apologized for ‘not being great with astrology.'”
He Didn’t Learn The First Time

“I was out working on building a shed with my dad, my uncle, and my cousin. Once we decided to take a short break, my cousin started looking for a chair but instead found an old car battery that was removed because it was leaking. After a few minutes later, he was wondering why his butt felt like it was on fire. The battery acid ate through his jeans and underwear and burned his skin. He then proceeded to touch the battery acid and burned his hand too.
My dad was looking at him and wondered how he was functioning as a person. Later the day he sat on the same battery but with something covering the acid so he won’t get burned again. Didn’t work.”
Come On, Brody

“My first job out of high school was at a lumber yard. There was one particular job where we had to take boards from the cut trees (they weighed quite a bit due to the moisture still in them), and stack them on a cart to be moved to the yard. The boards we were running were 14’-16’ foot long, and anywhere from 6”-24” wide. They could weigh anywhere from 100 pounds to 300 pounds.
So the last board comes down the line and it’s huge, 16’ long and at least 20” wide, weighed every bit of 200+. The new guy, ‘Brody,’ had his name written on it, so as he went to try to get the board on the cart the only spot left was a 10”.
He fought for the life of him to get this wide board in their tiny space. He slid the board on there; wrestled on the side in but couldn’t get the other side to go so he’d take it off and try it another.
After five minutes of watching him struggle, he finally asked why it wasn’t fitting on the cart. My supervisor tossed a tape measure at him and Brody proceeded to ask how to use it.
Became the running joke for the company until he was fired.”
Get This Kid Away From Machines

“I work in a large furniture factory. There’s lots of machinery that could injure you very badly, and even kill you.
I had been there for about two years at this point, and I’ve seen so many people come and go; the turn over was insane. There was this one kid who always seemed to be not the brightest. I tried to give him the benefit of the doubt and stop being so critical.
He ended up turning on a blade and sticking his hand into it. The machine is basically a router table, but the router bit isn’t just sticking out of the middle of the table; it was attached to a raised back edge on the table with a shroud over it. There’s an off/on switch on the side of the table. You can see the table is clearly plugged into an electrical outlet.
Anyway, this kid came over to the table and wanted to know what it was. Instead of asking someone who had worked there longer than him, he decided to flip the switch and find out himself. He heard a noise startup after he flipped the switch on, and figured that was our air vacuuming dust collection system. Then he decided the best way to get the answers he wanted was to obviously stick his hand in this loud strange hole.
He ended up with minor injuries but refused to take a substance test after the incident, so he was moved to a position that doesn’t involve any machinery.”
This Woman Was So Wrong

“I was on a 12-hour flight with someone who’d never flown before.
The real point it hit me was when we were a couple of hours from our destination. We lower in attitude, and she notices something outside the window.
‘Oh my god there’s icebergs!’ she exclaims.
What? Keep in mind, we’re flying to the Middle East and we’re above the Mediterranean, there’s no way there are icebergs.
I look outside and realize in a moment of both disappointment and pity and respond ‘No, those are clouds.’
I would have forgotten most of the experience after but she defends herself.
‘Those are clearly clouds,’ she declares. ‘I don’t understand I thought we were going to a desert how are there icebergs? Is the water that cold?’
She not only refuses to listen to my pleas that they’re in actuality clouds but then continuously asks me for reasons why they’re impossibly there.
I eventually give up and just stop talking and leave her to her rambling, knowing eventually we’ll go below them and she’ll understand then.
We start descending and, once our plane flies through her icebergs, she finally goes ‘Oh they’re clouds. Oh, were you just being nice?’”
It’s Kind Of Hard To Miss

“I started dating a girl I knew for a few years. One night while hanging out and just talking about random things, it came out that she didn’t know what Alcatraz was.
Keep in mind, we are from the Bay Area and see Alcatraz all the time. It’s a staple and icon of the area. There are shirts, tourist traps, movies, books, signs everywhere. It’s like knowing what the library is around here, besides being a landmark known worldwide.
I just looked at her like ‘Wait… huh? You don’t know what Alcatraz is? The prison on the island right there?’
She had no idea.
It completely changed my perspective on her, and everything fizzled out from there.”
There’s So Many Things Wrong Here

“My supervisor and I were talking about weird historical things, and one of my co-workers started asking about some stuff.
She said things like, ‘Is Rome where Egypt happened?’
While we tried to figure out what the heck she meant, we found she apparently associated ‘Egypt’ with ‘all of those guys racing around in circles, with the horses, and the big tower thing in the middle.’
I guess we said something about Rome, and she was really curious?
She also asked several times (several times) asked if Atlantis was real. Not, as I found, whether there might be an ancient underwater city somewhere which may have been known in ancient times. She wanted to know if Atlantis from the movie Aquaman was real, with people swimming around in it.
She also claimed she had been pulled over by the police something like 96 times, which made it so that she had to pay 600 dollars for car insurance every month, on a normal car.
She was very bad at her job. Yet had the endless, unwarranted confidence of some combination of a six-year-old and a complete psychopath.”
Seven Was Impossible

“I’m in the Navy and at one of the commands where I was stationed, we had duty sections that would take care of various command functions each day. Now a lot of places in the Navy will either have six or eight duty sections so they’re constantly rotating throughout the week.
I was temporarily assigned to somewhere else for a little under a year, and when I came back to my home command, I couldn’t remember if we were at six or eight sections and asked one of my co-workers.
He told me we were at seven.
I wondered if he misunderstood my question and I told him seven sections were impossible because if two sections were constantly stuck working Saturdays and Sunday and no one else had to, that would be incredibly unfair and would probably lead to a mutiny. I also told him that if you had seven sections, it would be impossible for them to rotate throughout the days of the week.
He kept insisting that we were at seven, even after I asked him what days he had duty that month and they were different days of the week. I then had to pull out a calendar and manually count the days to him to prove how seven sections wouldn’t work.
He still was not convinced, so I called another of our co-workers and asked him. He told us we were at six sections.
He was a nice guy but he was absolutely dumber than a rock. Oh, and he was also in charge of pay and other high-level admin functions.”
Maybe She Should Have Done Her Job

“So a small part of my job is reviewing cases to find any potential problems that might occur. A secretary is responsible for getting all the paperwork together for me to review, but unfortunately, she isn’t very competent. These cases happen on Monday and Tuesday, so I review them the Wednesday and Thursday the prior week.
I have been having a lot of issues with this secretary getting things ready and getting preliminary information completed, sometimes not getting it at all. One week, I was scheduled to take off Friday. So on the Thursday before the cases, I go in to get Tuesday’s cases. They aren’t ready of course, and the secretary says to come back tomorrow (Friday when I am off). I inform her that I am off Friday, so I won’t be able to review those cases.
She says with a sassy attitude, ‘Well then you should have come earlier in the week.’
I then point out that it was Thursday, the cases are not ready, and it would be pointless for me to ask for them any earlier.
The look on her face was priceless when she realized how stupid she just made herself look. I also want to point out that I have told her, and her boss and management, that these cases should be completed two weeks in advance, not the week before, to allow for any corrections to be made.
The secretary and her boss looked at me like I was a mad man, but management agreed. There are about six other offices in these groups that do it at least two weeks in advance. It is only this particular office that has problems.”
She Would Know, It’s Her Job

“Years ago, I was over at my (now ex) boyfriend’s house with his family for dinner. His mother worked in healthcare, his father an engineer. At the time, I was working as a lifeguard and teaching swimming lessons at a local pool. The ex was working as a cashier at a pet store.
My ex was the type who knew everything’ and would bulldoze over conversations constantly. So we were all talking and I don’t know how the conversation got to this point, but he kept talking over me saying he knew more about CPR than me. This was a little insulting as it was my job to know and he has never had his CPR certification.
So I finally got fed up with his bulldozing, and decided to ask him a question, ‘Okay, so if it’s possible for the human body to have a pulse but not be breathing, is it possible to breathe without a pulse?’
This idiot no joke sat there for a whole four seconds thinking, then proceeded to say yes and explain why that was possible. I honestly don’t even remember what he said after that, but all I can remember is looking over at his mother and seeing her face drain of all hope, sheer disappointment slowly to turning to anger when she meets my eyes.
I don’t think she liked me after that. But I died laughing telling my parents later.”
Write Down The Password Next Time

“Co-worker forgot her password to a system we use daily and asked for my help. I told her it was unlikely I could help but suggested she use the ‘forgot password; link so she could answer her security questions to reset it. She said that’s what she needed help with.
The question on her screen said ‘favorite historical figure.’
I asked her who that would that be. She replied that she didn’t have one.
I said, ‘But you get to choose which security questions you want to answer. Why did you pick that one?’
She didn’t know. She was getting frustrated, so I told her to take a guess. She types ‘none.’
Password reset. This chick specifically chose a question she didn’t have an answer to. I left her desk without a word.”
There’s No Way They Were Going To Pass

“I was in a Statistics course in college and there were some real winners in that class. The best two had to be these two girls who decided they couldn’t pass the class on merit, so they started flirting with the professor (who was really peeved about it). I mean, they wore very revealing outfits to class and leaned over his desk, they brought in store-bought cookies and such, etc. None of it worked. It just made him hate them.
One day we’re sitting there and learning the Greek symbols for certain formulas.
They pipe up with ‘Aww, you made up your own language! That’s so amazing! You’re so smart!’
They were serious. They had never in their 19-22 years ever heard of Greece or Greek culture. None of us could wrap our heads around it. They flunked out of the class at midterms.”