Matt Emmi: when should you listen to your customers?
"I think you should listen to your customers when you are focusing on evolving a product. If you are trying to come out with something revolutionary, that's when you don't want to listen to anything they say. I think Apple is a great example of this; nobody expected a phone with no buttons and a giant slab of screen. But then after they came out with the first iPhone, the successive iPhones were very evolutionary and they spent a lot of time listening to their customers at that point. So when you are trying to evolve, listen to your customers. When you are trying to do something revolutionary, completely disregard everything they have to say." -- Matt Emmi
See Article
http://www.fastcompany.com/3012091/30-second-mba/matt-emmi-when-should-you-listen-to-your-customers