If you try to develop ideas with an average customer you will end up with average ideas. But if you succeed in identifying and choosing a group that includes truly innovative or proactive members, you can expect more innovative products. These are the so-called lead-users of a product; they will identify deficiencies months or years before the majority of the market encounters them and they are considered to benefit substantially by obtaining solutions (in terms of product innovations) to those needs (von Hippel, 1998).
The difficulty with this method is to find the true leaders. One well-known car manufacturer has applied this method successfully with, for instance, the development of new brake technology; the leaders in the field appeared to be not in the automotive industry but in the aircraft industry.