I'll try and give you the reasoning without the sarcasm. The NBA rules prohibit the Rockets from negotiating a long-term deal with Yao now. All they can do is choose to extend his rookie contract for one season. At the end of this coming season, however, the Rockets will be free to negotiate (exclusively) a new long-term extension with Yao. Both Yao and the Rockets understand this.
kevin8494 is not alone in his thinking that way. Seems like the Chinese media is reporting that Rockets are extending Yao ming for another year and then he's free to leave for another team after that.
So, at what point are Yao/Rox done paying off the Shanghai Sharks and the PRC? Does he actually get to keep the proceeds of his next contract?
He will only stop paying PRC until he official retires from basketball unless he defects (which he will never do).