Lucas freely admitted circa 1979 that the primary purpose of the Star Wars sequels was to finance Skywalker Ranch and Lucasfilm. In fact, he talked about this openly and frequently, i guess because at that time he was a hailed auteur and had no need to hide any pretentiousness. Now however, with all the criticism he has recieved since, he has to pretend its for some glorious artistic statement, this whole "Tragedy of Darth Vader" thing, with an equally self-inflated title like that. Of course there is a high degree of sincerity in the prequels--there can't not be, given all the time and effort spent on it. But even now, Lucas still admits that one of the reasons he returned to Star Wars in 1994 was to re-claim the position of wealth--the wealth of the OT--that had been snatched away from him after his 1983 divorce.

"Then i decided one of the reasons i would go back to the star wars films [the prequels] was that they would make me financially secure," Lucas said to Charlie Rose in 2004. As for being detached, he is indeed, but i don't think at all to the degree his critics surmise. To be sure, he does indeed enjoy making the prequels and put all of his genuine effort into it, but he still works as a businessman and has the detached demeanor of a producer or executive, both of which are his primary roles in Lucasfilm and on the prequel films themselves. Thus, he is equally concerned with efficiency, cost-savings and getting stuff "good enough," as opposed to "good," which was the reason for the split between Kershner and Lucas and between Kurtz and Lucas. Now, with the prequels there is no one to keep him in check--the films are very efficiently and cheapl made, amazingly so, but the quality is kind of "meh," because theres no one there to give the artistic side the same amount of emphasis--and no one talented enough, for that matter.