Constraint

Wired magazine (March 2009) illustrates Design under Constraint, with examples including cell phone antennae, plastic bottles, and electric cars.

"But for all that we can't do in this static medium, we find enlightenment and wonder in its possibilities. This is a belief most designers share. In fact, the worst thing a designer can hear is an offhand 'Just do whatever you want.' That's because designers understand the power of limits. Constraint offers an unparalleled opportunity for growth and innovation.
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Given fewer resources, you have to make better decisions."

Return on Design

Seth Godin has an interesting post on Return on Design. His four categories:

Negative return. The local store with the boarded up window, the drooping sign and the peeling paint is watching their business suffer because they have a design that actually hurts them. Software products suffer from this ailment often. If the design actively gets in the way of the story you tell or the utility you deliver, you lose money and share.

No impact. Most design falls into this category. While aesthetically important, design in this case is just a matter of taste, not measurable revenue. You might not like the way the liquor store looks, or the label on that bottle of wine, but it's not having any effect on sales. It's good enough.

Positive return. We're seeing a dramatic increase in this category. Everything from a bag of potato chips to an online web service can generate incremental sales and better utility as a result of smart design.

The whole thing. There are a few products where smart design is the product (or at least the product's reason for being). If you're not in love with the design of a Porsche 911, you would never consider buying it--same as an OXO peeler. The challenge of building your product around breakthrough design is that the design has to in fact be a breakthrough. And that means spending far more time or money than your competitors who are merely seeking a positive return.

Read the rest of his post