In the paper, Stephen Nowlis, professor of marketing at Arizona State University, and his colleagues summarize three studies that sought to fill a research void with regard to consumer wait. "Although prior research has addressed the circumstances under which people choose to wait and the effects of a delay on such variables as moods or evaluations of service received, little research has been done on the effects of an imposed delay on actual consumption enjoyment," the authors note.
The article explains that "a delay increases consumption enjoyment for pleasurable products when actual consumption occurs, but decreases enjoyment for imagined consumption."This was made salivatingly sure when study subjects were forced to wait a half-hour between choosing a chocolate candy and actually being able to eat it--even though they could see it. The subsequent enjoyment was pretty significant.
Journal of Consumer Research