People in management positions often find it difficult to deal with human errors. Simple reactions like asking people to be “more careful” very rarely bring any improvement. The seemingly easy solution to add warnings in documentation usually turns out to have a very limited effect. Another natural reaction is to try to train people more, hoping errors would then be avoided. Whereas different technical and non-technical skills can be improved by training, therefore having a positive impact on certain types of mistakes, training does very little in preventing slips and lapses.
Therefore, one must accept the fact that errors cannot be completely prevented no matter how much people are trained and how many warnings are put in the operational documentation.