How hard it is to follow instructions?

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Instructions can be seen as guidelines that need to be followed in order to complete a certain task. From a first point of view; it is easy, right? However, most of the time; there are complications that block people from accomplishing this task. 

Either the instructions are not clear; or the person following does not have enough knowledge about the subject. So how hard it is to follow instruction? Several guidelines need to be followed. It is important to follow each step accurately; have all the material needed to complete the task; be patient and do every step with attention to detail. 

The most important thing to remember is that instructions are made to make things easier and not complicate them.