Jason Zimdars believes sometimes not shipping is a virtue. He goes into how one Basecamp features he designed never actually made it into the product, and what he learned from it. This quote is so good:
Every feature has hidden costs. Some are worth the cost—sometimes many times over—but others only drag your app into the red. One more thing on the screen you can click, one more option, another setting, more decisions for users to make (Kathy Sierra calls this cognitive load). Your app gets slower and customers notice it feels slower. Designers have to juggle more pieces. Development gets more complex, difficult, and time-consuming with every new piece you bolt-on. That’s a lot to ask of a feature that’s only fine.