Very true, I have always had the same perception maybe even treated it as an undisputed cliché in every startup pitch.
But as time goes on, I seem to be getting more cynical to the perception and start believing a lot of the ideas are just more successful because of the 'market analysis' done before hand (with the exception of trend-makers, for example AirBnB)
Look at Blippar for instance, the startup that triggered this realization when I heard about it.
Augmented Reality has existed for quite some time, there have been countless applications, from real estate to navigation, yet many of similar start-ups have faded as time went on, but they on the other hand have remained due to targeting a cash rich market (Advertising) even though it solves no problem.
I know the above statement is quite simplistic, and surely it does not make the Blippar team justice for all the effort, strategies, etc that they employed. However, the idea of (what I perceive to be artificial) and yet has been so successful in such a short period of time is a bit of an eye opener.