(This is highly unscientific, which is basically what you've come to expect when the name 'Ziller' is involved.)

Look at the four conference finalists from 2008. How'd they get there?

Except for the Spurs, all these teams got to the peak via trades. Detroit's trades for Hamilton and Wallace aren't considered to be on the level of the acquisitions of Gasol or Garnett, but they were still important. San Antonio's the only "homegrown" elite team.

Let's look at 2007:

Again, the Spurs did it through the draft. Cleveland, also, got the central piece through the draft. Give half Utah's credit to free agency and half to the draft — note that they did make a trade to get the #3 pick in 2005.

And finally, 2006:

What's the lesson, if there is one? It's very hard to create a championship team relying on just one part of the game: only the Spurs have done it. And the draft is pretty damn important: only the Celtics and Pistons can say none of their top-3 players were drafted by the team … and teach team's fourth best player was a hometown draftee.