When a promising product is announced, it goes through four stages according to Gartner. #1: the peak of inflated expectations, #2: the trough of disillusionment, #3: the slope of enlightenment and #4: the plateau of productivity.
The Hype Cycle starts out with an innovation that catches people's attention and rises quickly to the "peak of inflated expectations." If progress is not made quickly enough, it falls into the "trough of disillusionment." Later on, if the technology does have merit and begins to show commercial viability, it climbs the "slope of enlightenment" to the "plateau of productivity." See
Gartner.