Not only stupid people make errors!


A lot of people think that if you’ve been really well trained to do a job, then you won’t make errors. This also leads people to think that if someone does make an error then it was their fault and they need to be retrained. Or, if the error is really bad, people might think that they’re not capable of doing that job and need to be replaced. But actually this is hardly ever true.

Everyone makes slips, and we make them everyday, no matter how clever or highly trained we are. Sometimes the environment we’re in (and that can be the physical environment as well as our ‘mental’ one if we’re really busy and distracted by lots of competing tasks) can make it much more likely that we’ll make errors.

Sometimes slips are just a bit funny and embarrassing – we’ve all pushed a door marked pull or pulled a door marked push. But sometimes they’re really serious like a nurse giving a patient ten times the dose of medicine and making that patient really ill, or worse. Other times, they may just be simply annoying – like pouring orange juice into our cornflakes even though we’ve successfully added milk before.


You might not think there’s much in common between trying to push a door and giving a patient too much of a drug but the reasons people make errors are often very similar.  In the door example someone pushed the door but only really pays attention to it when it does something unexpected, which in this case is it didn’t open. In the nurse example a nurse pressed the alarm silence button three times on a pump to silence the alarm, the unexpected thing here came to light later when they found that this wasn’t the ‘silence’ button but ‘raise the rate of the drug’ button. In both cases the person intends to do the right thing, they expect the device to work a certain way, don’t attend to it completely, and a surprise happens when it does something different.

Our brains are designed to be efficient when interacting with the world, but they don’t always get it right. Just think… if we had to attend to every little detail, and treat everything like it was strange and new then we’d hardly get anything done. What if every door we entered was treated like something we hadn’t seen before – how do we negotiate this obstacle? Do we touch it? Do we speak to it? Do we perform an action in front of it? If we do touch it what part might we touch? If it moves does it slide? What way does it slide? Might it just fall down? These questions rarely occur to us because our brain is used to the pattern of a door, and what it does, and it just gets on with it. Sometimes it is so used to it that our brain does everything without us really getting involved (us in the sense of our conscious selves)! For example, travelling to work or school can be so boring and mundane that when we arrive there we find that we cannot actually remember how we got from A to B. If something out of the ordinary or an emergency happened then our brains would have called on us to take notice and make some decisions… but normally they can get on with it and we day dream or think about something else.

It’s true that when we’re doing something risky or with a high cost then we might pay extra special attention to what we’re doing. For example, just before we book flights for a holiday we might get a friend to check that we do actually have the right dates and not the wrong ones.

“Before booking a flight I always get someone else to check the details, in fear of accidentally booking the wrong date or airport” – Resilient Strategy #16

These sorts of double checks are also performed in healthcare to make sure patients get the right dosage and that surgeons don’t forget things and leave them behind in people’s bodies. But these checks are not always made and what seems of high risk and high cost to us is sometimes just normal and mundane to nurses and doctors. For example, if they have to perform the same procedures over and over again, day in and day out, and nothing ever goes wrong… then complacency can set in and someday it could go wrong. This is why people in safety critical professionals must remain mindful of error – it could happen to anyone at anytime, so beware!

Of course, sometimes it has nothing to do with complacency – we might be in the wrong place at the wrong time and there’s little that can be done to avoid error. Sometimes it might be that individuals are under stress and fatigued so they miss things in the environment that they might otherwise have noticed, leading to something going wrong. It’s not all doom and gloom though… in our related articles we describe how technological changes, system changes, a learning culture and resilience strategies can all contribute to a less errorful and safer world.

If you found this interesting, maybe you’d like to take a look at some of the other stories and articles in our Learning Zone?