One of the reasons why experts need the ghostwriting service is the fact that they don´t realise how much more they know about their expertise area and/or subject compared to others. While the general public may have a great interest in that area or subject, it understands almost nothing about it. It means it needs to have some basic concepts spelled out before it can begin to understand the details.
With the same level of knowledge as the average potential reader, the ghostwriter knows what questions to ask, and knows when the expert´s arguments and explanations are too complex and need to be simplified.
A ghostwriter can be an enormous help in turning the expert into a great teacher, in being the one who translates the knowledge within the expert´s head into a language that others with none of that knowledge can understand.
1. explain things in terms that are familiar and in everyday use.
2. keep it simple! Do not underestimate the meaning of simplicity.