I've had the Wired interview with Fred Brooks sitting around since last summer, awaiting an opportunity to blog about it. He's got a long history with technology and is now writing about design. I enjoyed this quote, as it has to do with constraints.
Brooks: The critical thing about the design process is to identify your scarcest resource. Despite what you may think, that very often is not money. For example, in a NASA moon shot, money is abundant but lightness is scarce; every ounce of weight requires tons of material below. On the design of a beach vacation home, the limitation may be your ocean-front footage. You have to make sure your whole team understands what scarce resource you’re optimizing.
I've seen variations on this sentiment in other design-related writing. And, of course, I appreciate the idea of constraints from my work in Theory of Constraints. The use here is a very specific constraint: you can't get more lightness without spending a whole lot of money. And similarly, you can't get more of your constraint in business without spending money. So, you do everything you can to do the most with what you have.
Knowing your constraint helps drive the solution. Not knowing usually means you are applying the wrong solution in the wrong place.