The Field Guide to Understanding Human Error, 2nd Edition

5 “They Should Have …”

It is so easy to say what people should have done. Or to say what they shouldn’t have done. With the benefit of hindsight, you can easily see what people could have done to not have an incident or accident happen. You may even think that this explains the mishap; that you can understand human error by saying what people should have done or did not do. But this is an illusion. As soon as you say any of the following:

• “they shouldn’t have.”
• “they could have.”
• “they didn’t.”
• “they failed to.”
• “if only they had.!”

you are quickly gliding away from the possibility of understanding human error. We can call these phrases counterfactuals. They are literally saying something “counter the facts”. ...