Ephemeral adaptive interfaces use a combination of abrupt and gradual onset to provide initial adaptive support, which then gradually fades away. The goal is to draw the user’s attention to a subset of adaptively predicted items, in turn reducing visual search time. The following figure applies ephemeral adaptation to a menu: adaptively predicted items appear abruptly when the menu is opened, after which the remaining items gradually fade in.
(Source: Findlater, K. Moffat, J. McGrenere, J. Dawson. "Ephemeral Adaptation: The Use of Gradual Onset to Improve Menu Selection Performance
". CHI 2009