I'm always doubtful. Everything I do is always doubtful. When you're trying to differentiate, there's going to be this gut sense, is this right? If you're not having doubt, then you're not pushing it hard enough, or you're not looking at the details close enough. You need to be feeling that doubt every single day.

It's easy to solve a problem that everyone sees, but it's hard to solve a problem that almost no one sees.

We built the iPod in weeks. It had to be what I thought it was going to be because there wasnt time for endless refinements.

When I encounter a problem - something that's not quite right with a product - I enjoy breaking it down in my mind and exploring possible alternative solutions: Why this? Why not that? I apply the latest in technology and design to reinvent that product and solve my frustrations.

People buy products, and they want to understand what those things are and how they are applicable to their life.

Learning by doing is the only way I know how to learn.

We're thrilled to join Google. With their support, Nest will be even better placed to build simple, thoughtful devices that make life easier at home, and that have a positive impact on the world.