I ran across a great segment of Steve Jobs talking at the WWDC in 1997 just after he returned to Apple. Similar to my post about pruning the decision tree, he speaks about the power of saying no to the bad ideas. "Focusing is about saying no," he says. His analysis of what was wrong with Apple at that time was that they had terrible engineering management. They were doing too many things--interesting things--but had no direction. When he took over, the decisions that had to be made were not to cut things that were bad, but to cut things that were unfocused. A lack of focus makes the whole less than the sum of the parts. Good focus allows the whole to become greater than the sum of the parts.
Two segments are worth watching. The first is Steve Jobs explaining his philosophy:
The second is him responding to a question about why they cut OpenDoc. The interesting observation is that OpenDoc was probably better than anything else at some things. That, by itself, wasn't enough. It had to be part of a larger vision or it had to go.
He ends with a great observation about how you have to let the vision dictate the technology and not the other way around.