Visual User Interfaces (VUI) are information dense. They allow users to skip ahead or scan for keywords. They provide pictures that are — as the saying goes — worth a thousand words. In this sense, VUI has an advantage over Voice User Interfaces. Voice is a linear stream of information. Users lack the option to scan or skip ahead in the stream like they could with VUI. They are (mostly) forced to consume the entire stream of before taking action. As mediums go, Voice lacks the information density and accessibility of visual interfaces.
Voice information density and accessibility is a long-standing Voice first problem. At TsaTsaTzu we essentially use the Method of Loci (MoL) and other Voice UX tools to boost the information density and digestibility of Voice. We impose information hierarchies through classification structures (rooms) that can be explored.
For example, you might organize a hypothetical Cat Trivia voice app into subheadings like Abilities, Personalities, Companions, etc. You turn your classifications into separate rooms — geographies — within the MoL approach. Then you inform your users about what kinds of content is accessible. You let them walk from room to room, exploring the options. What to learn about cats that can safely bond with dogs? Visit the Companions room. Or you could create a room to be a site map — say an elevator or transporter room — to move users between distant rooms. In these ways you make the organization of content tangible, into a representation that is richer and more accessible than other approaches.