“What do your designers actually do day-to-day?” → they design!
Mockups are usually quick sketches on paper or on the iPad. Low-fidelity. Sketches only need to communicate intent — they do not need to communicate detail. So time spent prettying them up, or getting them just perfect is wasted time.
We try to get to HTML/CSS as quickly as possible. Or, on mobile, a working prototype as quickly as possible. We want to use the real thing, not a representation or abstraction of the real thing. We want to get real as quickly as possible so we can judge the actual experience. Simulated experiences always something, and often times that something is the real truth in a design/experience. You’ve got to really use it to really know if it’s any good or not.
We don’t have scheduled user feedback sessions. We do the best job we know how to do. And then we ship. Customer feedback is then real feedback — real people using the real product for real things. No simulations. If we need to adjust post launch, then we do.