The longevity of general purpose Wizard-of-Oz tools

The Wizard-of-Oz method has been around for decades, allowing researchers and practitioners to conduct prototyping without programming. An extensive literature review conducted by the authors revealed, however, that the re-usable tools supporting the method did not seem to last more than a few years. While generic systems start to appear around the turn of the millennium, most have already fallen out of use. Our interest in undertaking this review was inspired by the ongoing re-development of our own Wizard-of-Oz tool, the Ozlab, into a system based on web technology. We found three factors that arguably explain why Ozlab is still in use after 15 years instead of the two-three years lifetime of other generic systems: the general approach used from its inception; its inclusion in introductory HCI curricula, and the flexible and situation-dependent design of the wizard's user interface.