Malcolm Gladwell is an author that has written a number of books including The Tipping Point and Blink. In his books he breaks down concepts like how we make snap decisions or what makes us want the things we want. The Tipping Point focuses more of why we make the choices we do and I highly recommend reading it if you are looking for an interesting book.
In this clip, Malcolm explains the revolution in marketing from focusing on trying to make the perfect product (such as the perfect mustard), to making a variety of products that please different types of people (such as spicy mustard, grainy mustard or classic mustard).
It will give you a deeper appreciation for why there are so many varieties of products now. I used to find it frustrating when I shopped because I'd have to sit there and debate which version of the product to get (when there are 9 options or more). Now I embrace this part of our culture because while you may be an extra chunky pasta sauce lover, I would be very sad if I couldn't get my extra spicy.
Follow this link here for the video: http://www.ted.com/talks/malcolm_gladwell_on_spaghetti_sauce.html