"A mediocre idea that generates enthusiasm will go further than a great idea that inspires no one." - Mary Kay Ash
The best ideas still need selling! Your enthusiasm is what closes deals. Great concepts can be lost easily if they are pitched without excitement. Bad products are sold everyday because of a sales persons approach. If you need some proof, watch a few infomercials. You'll usually find a product that isn't revolutionary and a pitch man that sells hard to the contrary. The flip side is that many great ideas and products come and go because the person or people tasked with selling them lack that burning passion. When you truly believe in something, you'll sell it hard every day.