Presentation refers to the manner in which a routine or act is framed.
A routine performed with nothing more than a narration of the magical happenings, and the apparent conditions that make it seemingly impossible, is rarely sufficient to capture and keep an audience's interest.
The use of consistent characterizations and effect framing serves to generate and maintain audience interest, as well as making an act and performer memorable.
Harry Houdini consistently performed as an everyman who overcame incredible obstacles. By contrast, David Blaine performs as a mysterious stranger, and Mac King performs as a bumbling country bumpkin. Professional performers not only carefully craft their performing personas, but make sure that the effects and the framing of those effects they choose doesn't conflict with the image they're trying to create.