Imagine that you are standing in front of an audience, the room is getting quiet and everybody is looking at you to start your presentation. You begin your presentation and as part of the introduction you show a slide to your audience with the agenda. Now you realize it when you look at it… You have the wrong version of the slides. It is old… People are still entering in the room, surprised seeing that you already started your presentation. They didn’t receive the correct version of the invite with the correct starting time. Others may have received a version of the invitation with the wrong location… You take a quick look at the handouts that were printed for your audience. It is also an old version containing some errors that you corrected in the final version…
Version control of all supporting materials is very important. Especially when you work together with others, make sure that it is clear for everyone who has the master of the document and have a clear system for identifying subsequent versions of a document (version number + date), so it is very clear that for the actual presentation only final versions are being used. Avoid wasting time and embarrassment in front of your audience: use a proper version control system for all supporting materials.