Everybody makes mistakes now and then, but you always have to be careful not to make a huge mistake. For these employees, they're thankful to still have a job.
(Content has been edited for clarity.)
The Customer Wasn’t Expecting Their Car To Be In A WORSE Condition After Leaving It At The Shop

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“A respected service technician that I know managed to wreck a customer’s $50,000 Ford SVT Raptor while doing a test drive after performing some routine work. He ran a red light, got t-boned, and flipped the thing six times. The insurance company really loved him for that. And the customer got a new truck (among other things). Luckily, in this particular case, nothing happened to the employee. In fact, the company even paid his medical bills for the incident. They’re a good business and the technician has been with them for several decades. He’s an old man now and I honestly think it was just a genuine lapse in judgment. Had it been a new, young and reckless tech though, things would have been different.”
This Client Was Not Thrilled With Their New Website

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“I once deployed an update to a client site to the wrong client’s site. Since it was a complete overhaul everything worked just dandy until the client noticed a website devoted to their competitor replaced their site…
Luckily, I was not fired.”
One Mix-Up Ruined A Patient’s Life

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“I used to work in the pathology department at a major US medical center. A coworker once caused a case of cross-contamination where biopsy material from a patient that was positive for cancer was mixed into a biopsy of a lymph node from another patient’s neck.
This caused the cancer-free patient to undergo numerous rounds of chemotherapy and radiation treatment and, eventually, the patient had a radical neck dissection (surgeon essentially takes out all the lymph nodes in your neck to see how many/which ones are positive for metastatic cancer). It was only at this point, where all the lymph nodes were found to be benign, that people realized something was wrong, the case was investigated, and it was tracked back to the initial biopsy.
Besides the horrible few months that patient must have gone through, I’m sure the hospital got sued for at minimum several hundred thousand dollars, most likely millions.
The hospital made a lot of changes to its processes afterward to include additional safeguards. It is VERY easy for something like this to happen if you are not careful, especially in a busy lab like that. But the mishap was inexcusable, and even if it was an ‘honest mistake,’ our whole job depends on not letting these things happen, and they should have been canned immediately.
But alas, the co-worker never got fired. I don’t know how they are able to sleep at night, just the thought of it still makes me sick.”
Ruining The Wedding

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“I’m a Wedding DJ and I’ve ruined an entire wedding before because of a mess up. Right in the middle of a Father-Daughter dance, my amp died completely. I couldn’t get it to come back on and didn’t have any backup equipment. Luckily the Bride’s father had some DJ equipment that he used for Tailgating parties, so he ran home and got his gear for me to use for the rest of the night. I ended up refunding them as it didn’t feel right getting paid for a job that the client wasn’t happy with.
Learned my lesson the hard way: be prepared for anything.”
His Mistake Was About To Blow Up In This Chemical Plant’s Face

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“This happened to a coworker, but holy smokes was it a doozy. He almost blew up a manufacturing plant.
I work for a manufacturing/engineering firm that provides industrial airflow equipment. We had a reseller call in and order an air blower from us, but there were a lot of warning signs in the order that showed they didn’t know enough about what they were buying. My coworker, ‘M,’ should have caught this, but he’s lazy, and just sent it on for processing.
A couple of weeks later, they called in to order another one as a backup. One of our better employees got this one. She noticed they seemed to be asking for the wrong equipment and sent it up to me for review. I called the guy to discuss and lo and behold, they needed some specialized gas handling equipment and not a typical air blower.
We started talking safety and the original product they got wasn’t gas sealed, so it was going to leak whatever it was processing. They happened to be processing a highly explosive gas mixture, which might have been manageable if it wasn’t in an enclosed space and not the 10′ by 10′ room where it was installed.
Oh yeah, they had electronics and sparking tools with open flames in there as well.
They needed to shut down the plant immediately, which was not great as the entire facility requires this process to be operational and they’d lose something like $1M per day of downtime.
Also, since lives were put in danger, my company viewed the incident as negligence by laziness, yet my coworker was not reprimanded.”
He Had No Idea How Rare Those Samples Were

“I work in a research lab where we dealt with a lot of human and other animal tissues for such procedures like DNA/RNA extractions for further testing or other molecular protocols. My boss had been complaining over the past couple of weeks that the -80 degree centigrade freezer needed to be inventoried and to toss my really old stuff. So one weekend, I decided to be a good worker and clean the freezer!
There was a rule in this lab: if something is not labeled, throw it out, how are we supposed to know what it is? Notice I didn’t make that rule, it was just there.
In my haste, I tossed an unlabeled box with a number of small tubes containing samples. That Monday, I got a frantic call from my boss asking me where the unlabeled box in the freezer was. It turns out that there were multiple heart samples from a teenager who had died. In research, it’s rare to get a human sample like that from a young person unless they passed. At that age, nothing really should be wrong with the heart, so the amount of tests that can be run/data that can be produced is amazing.
The rest of the staff did support me, calling my boss out for not labeling the box, but I still won’t forget that I essentially threw away a heart.”
Messing With Lab Equipment

“Our labs use gas chromatographs, a large part of which has to be kept at a specified temperature in an oven. One of these machines keeps having a sharp drop in temperature when left to run overnight, ruining the samples being tested.
Our people tinker with it, and they don’t find the problem. They call customer support, they’ve never seen this issue, and they don’t know what the problem is. Customer support sends out an engineer to look at it, but he still can’t find the problem. He decides to stay up with it during the night to see what happens when the temperature drops.
As the time approaches, a janitor is cleaning the area. Eventually, the janitor comes into the lab. He opens up the instrument oven and puts in a frozen TV dinner [facepalm].”
They Let A Hole Burn In This Company’s Pocket

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“I was fairly new on the job at a help desk office. Someone was going to lunch and asked me to keep an eye on their monitor and watch for a red bar, then let IT know if it came up… but it never came up, so no big deal. Well, I wasn’t paying attention and the red bar indicated that the ATMs at a few hundred banks were going down and I didn’t notice. The losses were estimated to be over $1 million. I got a good scolding.”
Getting Arrested

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” I was driving a work supplied courtesy car whilst mine was in the shop to repair brake pads. I decided to go shopping in the middle of the workday, so I drove to a shopping center 5 miles away to attack a sale at my fave store. Whilst trying to find parking, I hear police sirens and I am cornered by 5 police cars in the middle of traffic. One of them jumps out and asks me to quickly and calmly pull over. I do so and ask what I have been stopped for (all the whilst I’m crapping my pants). Officer asks for proof that the vehicle is mine but I have none. I explain that it is a courtesy car that my employers have given me but I’m too scared to ask them to call my employers and verify this as I am meant to be at work.
So without sufficient proof, they arrest me, tow the car and take me to the police station. The reasoning is because the car has been reported stolen.
They ask me again to verify the car, so I tell them to call my manager as the worst is probably over seeing as I’ve already been arrested.
I hear them chatting away, the officer starts laughing and then passes the phone to me. I hear my manager scream ‘You are freaking fired you hear me?! FIRED!’
I pass the phone back and they release me, without the car.
I manage to get back to work where my manage greets me in fits of laughter. With further investigation, it seems that the previous driver (also a fellow employee) parked the car in a red zone without realizing, came back to find the car gone and reported it stolen. Once he realizes it had been towed, he got it back without informing the police. So for 3 months, the police had been looking for this freaking car.
Nevertheless, I didn’t get fired, just a good telling off and I am now known at work as GTA.”
Someone Didn’t Get The Memo In Time

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“One of my first jobs out of college was working as an analyst in the telecom department of a Fortune 500 company. We were going through a request for proposal to find a new supplier for voice over internet protocol services, so we were dealing with some major corporations.
As it came time to award the multimillion-dollar contracts, my boss went on vacation and left me a to-do list, complete with award/non-award letters to send out. I did as I was told, and a couple of days later my boss’ boss messaged me, saying, ‘Hey, FYI, we reopened negotiations, so hold off on those award letters.’
Well, it turned into a whole ordeal. The legal team had to get involved to figure out just how binding my letters were, and they ended up playing it off like I was some bumbling intern who accidentally sent false positives to every supplier. It derailed the negotiations, so they ended up missing out on some savings, but other than that, nothing much happened, and I transferred out of that department as soon as possible.”
They’d Pay The Price To Fix This Big Mistake

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“My boss forwarded me an email that, unknowingly, had a ransomware virus embedded. I opened it and spread it to all of the computers, including the server at our office. We lost every single important file that had to do with the five companies my boss owns. Thankfully I found a company that specializes in decryption that could get our information back, but they based their pricing on ‘How fast do you need it back?’ Because it was the day before Christmas Eve and everyone would be away for Christmas break, we chose to pay the premium $5,000 fee, which would make it so they would consider our case top priority. It was such a relief when they got our information back 20 minutes before I was planning on closing the office for Christmas break, but yeah, that was not fun…”
A Serious Case Of The Mondays

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“I run monthly reports to terminate inactive users on our system. It’s mostly for security, but also to minimize costs associated with licensing their various products. We were getting close to our cap on some products, so I was feeling extra brutal on my slashing.
Well, there was a glitch in the application programming interface that fed back dates on last activity. I sorted their accounts, popped them in a script and let the script terminate a few hundred people. Yes, the number was larger than usual, but I had also made the tolerance smaller, so it made sense. I walked away to make tea.
Ahem. Suddenly, our system database was getting significant call volume. I shrugged it off. It’s Monday; they did stuff over the weekend. Well, next thing I know, people are messaging me – any changes to licensing and access? Oh crap.
I quickly ran a reversing script, but not before terminating a bunch of executives and higher-ups. They were all forgiving but told me not to take the next ‘we’re cutting costs’ email quite so literally.
The second worse part about it was that we had recently created secondary processes for terminated accounts. This secondary process set new passwords and stripped out any device access. Basically, ten extra steps were completed automatically to secure devices. Everyone had to be reset on those devices, and new licenses had to be assigned… by hand.
Not the best start to the week.”
Can’t Lose That Customer Service Smile, Even For A Second

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“Working at Dairy Queen, one of the more popular things we made were chocolate dipped cones. For the most part, these things were easy enough to make, you put the ice cream on the cone, dip it in the chocolate for a few seconds, let it harden, and then give it to the customer.
At work I try to always have a good mood, I really do, but this particular day was busy and I really just wasn’t having it. A woman comes in, I politely greet her, and she pretty much ‘demands’ a dipped cone. Slightly irritated, I make the cone, dip it, and hand it to her.
Occasionally, the chocolate in the bin will run low and a manager will fill it back up, but the manager wasn’t there and again, it was busy. I knew the chocolate was low, so there was about a half inch of ice cream exposed at the bottom after I dipped in the cone which shouldn’t have been that big of a deal.
However, when I handed it to her, I immediately got, ‘Ummm hellloooo? Can you dip it ALL the way?!’ and she rolled her eyes. Again, not in the best mood, I go back to the bin and smash the cone into the chocolate so it is fully dipped and a bit deformed and handed it to her.
Turns out she was a secret shopper and told my manager. Oops.”
They Never Made This Mistake Again

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“I work in online advertising. I was managing a client’s ongoing campaign and part of that included updating budgets and end dates in the respective platforms one month at a time based on the upcoming month’s budget.
I updated the budget and the end date but failed to save the change for the end date. This led to us spending the client’s entire budget for the upcoming month in the final two days of the current month. That meant no budget was left over for the allotted month, and there would be no ads running through that entire month. We’re talking tens of thousands of media dollars blown in two days that were supposed to last 31 days.
My agency had to comp the client that media budget so that we could still run their ads through the month.
I didn’t get fired thankfully – At the time, I was the top-producing account manager on the team, so that helped me out a lot. Plus it was a mistake that every account manager and even the owner had made at one time or another, although maybe not to the same scale as mine.”
She Sent These Dementia Patients Into A Panic

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“I was a nurse’s aide and was in charge of the nursing home ward one Sunday. I thought I’d be an overachiever and make proper bacon and eggs for the residents instead of the sloppy re-heated stuff.
Yet I made the mistake of thinking the vent over the stove was functional. Bacon is pretty… smokey. The fire alarm went off, and it was LOUD. Because it’s a nursing home, there is an automatic alert sent to the fire brigade. Within three minutes, firemen were climbing in through the windows, 30 dementia residents were running around panicked and the ward was heavily fined.
I never cooked there again.”
All Is Forgiven In This Messed Up Mistake

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“I work at a warehouse that ships all over the world. When I was fresh on the job, I was in charge of transporting boxes of nail polish onto a 40-foot container. There were 25 boxes which I accounted for before I started.
I got maybe 12 boxes in when I went for out for lunch. My buddy asked me if he could move a few boxes from the aisle so that he could grab something behind them. He assured me he would move them back to me when he was finished. I got back from lunch, I grabbed the rest of the boxes one by one and loaded them up. I finished up the day, left and went home feeling good.
Around 11:30 p.m., I was overcome with dread. My buddy didn’t move the boxes back. I remember seeing them in the other aisle and thought to myself, ‘I better remember those!’ I DIDN’T. I forgot to put four boxes of nail polish on the container. I started to panic and debated whether to call my boss and let him know, but I know that it is too late to do that. I started thinking maybe the container would be there in the morning and everything would be okay.
I got no sleep that night and started thinking about my options. I continued tossing and turning until I left for work. On the bus ride in, I was looking for other jobs because I assumed I would be getting fired.
When I got to work, the container wasn’t there. I thought to myself, ‘MY LIFE IS OVER.’ My boss got there, and I immediately broke the news. I showed him the boxes I forgot, and he shared my dread. That load was worth over a million bucks. My coworkers were upset, saying I blew their bonus.
I ended up not getting in any trouble. My boss said that he was glad I owned my mistake and not to worry. The owner came and assured me I wouldn’t be fired, and that I was safe. We worked out how it happened and how to ensure it didn’t happen again. A couple of days later, I found out that the client dropped us as this was the third mistake we made with them.
It has been two years since, and I’m still there. Thankfully, we got that client back!”
Their One Mistake Caused An Entire Store To Go On Lockdown

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“I used to work at a grocery store as the primary closing attendant for the self-checkout. The self-check attendant had a set of keys they had to keep on them at all times: keys to open the machines themselves, and also a key to a small locked case of smokes.
One night, those keys went missing.
It turned out they were stolen. When management reviewed the security tapes, they saw that two ladies had come up to me to purchase smokes. I unlocked the case, and instead of putting the keys back in my apron pocket like usual, I set them down on top of the case and knelt down to get the brand they wanted. While I was getting their smokes, one of the women picked up the keys and handed them to her friend, who put them in her purse.
I didn’t realize the keys were missing immediately, because right after that a coworker came to relieve me for my break. I assumed he picked up the keys, and he assumed I took them with me on my break.
But this ended up being a MUCH bigger issue.
The keys to unlock the self-check machines were unique and every store had a different key, or so we were told. When we reported the keys stolen, however, the higher-ups were forced to admit that this was not true: there were, in fact, only four different key patterns for all of the machines across hundreds of stores. This meant that there was a security risk for untold numbers of self-check machines; opening those machines gave access to all of the cash, so that was a major issue.
But it got better! It also turned out that the key to unlock the case was no ordinary key. It was what they referred to as a ‘2 key,’ which was the master key for the store: they unlocked every single lock in the entire building, with the sole exceptions of the safe itself and the room containing the safe. It’s unlikely that the women realized the significance of that key, but that doesn’t change the fact that the loss of that key was a massive security breach for the entire store.
All of the locks had to be replaced – not just on the main doors, but on every office, every stock and supply room, and every locking display case in a store that covered an entire city block – and new master keys made and distributed. Security had to be heightened at all stores in the chain because they didn’t know how many of them shared the same key patterns for their self-check machines. And while I didn’t even receive a verbal warning for what happened, it triggered a change in corporate policy that made having the self-check keys stolen from you a fireable offense.
All because of a few seconds of inattention on my part.”