We often work in spaces where the light has no texture or shadow at all. Recessed fluorescent boxes spray an even wash of light across the the entire space. We are told this is the best light for working. That it provides even lighting across the work plane. Yet, when it comes to light that is beautiful and inspiring, what do we think of? Not the light that strikes our desk at the cube farm I bet we think of light like this.
Contrast creates texture and interest. It's mostly found in natural light, but well crafted accent lighting can do the same thing. When you look around your home....what light inspires you? I bet it's not perfectly flat.