I used to think very similar to you, I mean Woz was the engineer! Jobs didn't build or design the ipod. But I have since worked with product managers, both good and bad. I have worked in companies and on products with a good vision and a poor vision. Being able to get a good idea for a product, envision that product, and guide people through the whole process of building that product and keeping that vision through everything is very difficult and is a useful skill.