The Legibility Gap

A previous article in this journal proposed visualization as a compiler in architectural design: a translation layer that converts expert knowledge into something that nonprofessional stakeholders can engage with, with cloud-based collaboration platforms as the infrastructure for genuine co-creation. We now pick up where that argument left off, asking whether access to better visualization actually produces better comprehension, and defining a new missing piece: the legibility gap. Current practice assumes that advanced visualization is enough to inform nonprofessionals about the qualities of the built space. Photorealistic rendering and immersive extended reality (XR) technologies have succeeded precisely in triggering perceptual shortcuts through which human intelligence builds convincing spatial narratives from incomplete visual data. This success is part of the problem. A more convincing image gives the viewer less reason to doubt it and fewer opportunities to notice what is missing. Virtual reality (VR) raises what clients will pay. Comprehension scores rise too, on questions someone else has written. Neither gain teaches a viewer to notice what an image leaves out. Each medium restructures the legibility gap, and it is the gap that we are now mapping. We propose visualization literacy as a missing layer: a property of the co-creation process itself, not of the participant. The process is what produces the capacity to read, question, and critically engage with what is being shown. This, in turn, has implications for how collaboration platforms are designed, how professional practice is structured, and where design education still has work to do.