If Chief Executive Leung Chun-ying makes the same kind of mistakes as his predecessor, then his administration will quickly find itself bogged down in a morass of recriminations and ineffectiveness.
But if he learns from Donald Tsang Yam-kuen's mistakes - and corrects the missteps that have got his own term off to such a troubled start - then there is every prospect of a successful first period in office, and a return to power in 2017 by direct election.
Leung has an activist agenda that he wants to implement over the next five years, so his top priority must be to achieve a constructive working relationship with the Legislative Council.
He needs to think about how and why his predecessor's administration began with such promise, but deteriorated so sharply. The problems of the Tsang administration began when the democratic camp made the mistake of vetoing the political reform package of 2005. The then chief executive's mistaken response to that error triggered the slide which followed.
Tsang could never bring himself to forgive the democratic camp for his legislative defeat and the loss of face which followed. From that point on, he made it clear that he regarded the pan-democrats as the enemy. He would in future seek to work only with those perceived to be 'friends'.
Later in his term when he needed democratic support for his policies, it was either withheld or grudgingly and incompletely given. In the meantime, the attacks on him and his team were relentless.