He started his presentation by showing a pie divided into about 12 different pieces. Each piece of the pie was a software module that performed some function of the overall product. He then described, in detail, the functionality of each pie piece. This took 90 minutes - about 89 minutes too long. After that he gave a demo of the product.
It was agony.
The presentation should have been done in the opposite order - first a demo and then the breakdown. I had never seen the software application before so I was not familiar with how users interacted with it or what users would accomplish by using the software. When the presenter was explaining the pieces of the software at the beginning I didn't understand how they fit into the "big picture". If he would have started with the demo I would have a better understanding of why the software was broken down into the different modules. The detailed description portion of the presentation would also have been much shorter since he would not have to explain why individual modules interacted with other modules. The module interactions would have been blatantly obvious to me if I had seen the customer demo first.
This concept of starting with the users point of view (or from the top) and working down to the smaller components works well to educate someone with a new product or concept.
I once worked at an assembly plant that assembled automotive air conditioning compressors. After I had worked there for a year my supervisor said I should start giving tours of the assembly line. The company frequently gave tours to vendors, students, customers, etc.. My supervisor said he would show me how to give a tour. I thought this was strange - I know the assembly line and I think I am capable of giving a tour. I didn't think I needed training. What he showed me stuck with me to this day.
He started the tour at the end of the assembly line. He showed the audience the finished, assembled compressor. He showed them where it was installed in a car and what other components it was connected to. Then he proceeded to the next-to-last assembly operation and showed the audience that procedure. He continued in this fashion until he was at the beginning of the assembly line where the tour ended.
He told me that he use to give tours starting at the beginning of the assembly line. People would start asking questions and he would always have to go over to the end of the assembly line to show people how the part in the beginning was used in the final product. He decided one day to start at the end of the assembly line and show people the finished product and work his way back. He said this worked much better since the audience first saw the finished product and could easily understand how the smaller pieces fit into the final product.