An enlightening simile from an article on iPhone:
"Searching on a computer, he said, is like going to a store, where the customers sees every product displayed, and can make comparisons, touch the products, even try things on for size. Doing the same search on a mobile, he said, but like trying to shop in the same store but "through a drive-up window." No matter how much stuff is in the store, you can only find out through the cashier at the drive-up window."
"The dilemma, left unsolved by the panelists, was how to squeeze the user through that window, past the cashier, to sample all the things in the store, without guilt, while still feeling grateful to the cashier who seemed, all along, to be standing in the way."