That's the question everyone is asking Porter Goss, the now-former head of the Central Intelligence Agency. Goss himself isn't telling; his best response, as Dick Polman reports, is that it's "just one of those mysteries"--a more interesting rejoinder, at least, than "to spend more time with my family." One run-down of possible explanations is here; they include dissatisfaction with Goss by his immediate supervisor, John Negroponte, and his ultimate (at least nominal) boss, President Bush, as well as various speculations as to involvement with Hookergate. Nobody seems to think that Goss himself frolicked with prostitutes, but it seems like some of his higher underlings did, and when it all comes out, the shame will flow upward.
Of course, there's only one really good response to the question Goss refuses to answer:
I will not make any deals with you. I've resigned.
I will not be pushed, filed, stamped, indexed, briefed, debriefed or numbered.
My life is my own.