Some people criticize the term ‘human errors’. First of all, because it may be considered a pleonasm, because one could say that every error is a human error… machines do not make mistakes. Secondly, it is often not clear if something is actually an error.

A human error can be defined as: “a departure from acceptable or desired practice by an individual that could result in undesirable or unacceptable results” (definition by R. Bea).

However, in many situations people decide to deviate from prescribed instructions in a way that, in the given situation, is completely acceptable and within common practice, but the results were unacceptable because a failure or unforeseeable event occurred. Should we call this an error? For instance, there is a log of timber on the road. A cyclist sees this log and quickly steers around the log (=desired practice). However, by doing so the cyclist changes to the wrong lane of the road (=undesired practice) and a driver coming from a side lane did not see that because he did not expect a cyclist coming from the wrong side of the road. The cyclist bumps into the car. One might argue that the cyclist made an error, because he was riding on the wrong side of the road. However, the majority of other cyclists would have made a similar choice, so should we really call this an error?

Finally, sometimes people deliberately deviate from procedures to actually avoid a failure. That is also one of the reasons why planes are not always on autopilot, because the pilot should be able to adapt to unforeseen events. But according to the strict definition, that would mean they make an error since they departed from the protocol.

So, all in all one could argue not to use the term “human errors”, but the term “deviations in human behaviour”. However, for this MOOC we will use the term human errors, because this is the most broadly accepted point of view.