“An expert is someone who has succeeded in making decisions and judgments simpler through knowing what to pay attention to and what to ignore.” -Edward de Bono
Product managers often must determine what aspects of the product that consumers value. The marketing folks will use their qualitative and quantitative techniques to try and understand the voice of the customer and pass on what they learn. If the product is a car, the respondents will tell you that they want better fuel economy, better acceleration, improved safety, comfortable seating, room for the luggage, etc. Since the beginning its been up to product managers to understand their target market and strike the right balance between product performance and cost.
The challenge in today's marketplace is making the performance/cost tradeoff decisions for evermore complex product, increasingly diverse consumer tastes, and increasing sophistication of competitors in making the same decisions. Moreover, the technology required to make the necessary leaps in product performance must be planned and developed, which ties up precious capital. Indeed, now more than ever, it is critical that the business is able to "Find the Signals and Ignore the Noise".
If product managers want to be experts in their domain, they must be able to make decisions based on the "true" voice of the customer. By quantifying the voice of the customer in terms of product value, product managers can make high quality decisions about future product because they'll be able to develop solid business cases for future product concepts and ultimately R&D expenditures.