Without speakers, there would be no professional conferences, continuing education or entertaining programs. It is mostly common sense and courtesy. No matter how renown or expert, speakers are still human beings. This means that they are unable to read minds. They need to be briefed on their audience, the physical layout and the objectives of the program.
Every speech entails an element of risk.
Speakers are comforted to know someone is managing the safety net. Each step is a collaborative effort between the speaker and the caretaker. Make reminder calls regarding any interim deadlines. Since arrangements are often made many months in advance, it is important to keep in contact on a regular basis. Make a final reminder call several days before the program.