Design for the scarcest resource

Fred Brooks in an interview in Wired:

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.

It's a very clear, succinct way to put it. Any (good) design is trying a set of parameters or constraint, and one of them will be superior to the others. Make that clear across the team.

It may be the time it takes to develop. It may be the time it takes a user to find what they need. It may be the real estate on the screen. It may be weight. But it will be something.