Corey probably set up his slide show in topics. That way, he would save time, as the topics would present a kind of "reminder" so that he didn't waste time thinking about which part of the presentation to explain at that moment.
These topics would even help you answer questions from your team members. This is because the members could ask questions based on the topics exposed in the slides, so the questions would be more direct and would make it easier for Corey to have a quick reason to answer them.