But to the best of my knowledge, he doesn't engineer the insides of the products. He doesn't work out how the scroll wheel will actually make song skip, or paus

But to the best of my knowledge, he doesn't engineer the insides of the products. He doesn't work out how the scroll wheel will actually make song skip, or pause, or play. He works out how it will look, how we will interact with it, how it will be presented, and why. [I'm generalising and condensing though