She quit because she owes $500,000.00 in legal fees, is why she quit. It's the only way the numbers work out.
It's a debt that's not going away and that the lawyers won't settle. I wouldn't, if I were them. It was a pisspot of work--very good work, too, considering the stupidity of the client in getting herself into the Troopergate mess and everything else--and they billed it fair and square. (You can bet they will charge interest, too.)
How in hell will she pay them half a million bucks? Not out of her measly pretax $125,000.00 a year as governor she's not paying them--not with a special-needs kid, and a bunch of stupid upcountry relatives always hanging around with their palms stuck out, not even with the free house. Not to mention that her legal bills will continue to climb. There is simply no way she can afford to stay in her job and not end up in bankruptcy.
Unlike most people stuck with a gigantic uninsured bill they can't pay, though, Sarah Palin has a perfectly sound Plan B. On the right-wing lecture circuit she can earn five figures per appearance--possibly even more--and on the book deal even more (just ask the Clintons)--much more.
She can't do all that and be governor. It's true the book will be ghosted, but that is not to be held against her. So was Hillary's, and it made Hillary rich.
Not to mention the legal fees will stop.
It's important to remember that Palin has to do this now, while she is a hot property. If she waits, if any one of a dozen investigations pans out (catching her, for instance, re-doing her house at public expense), if time dulls her shine with the Stupid Right, if some better sexier and above all smarter person miraculously appears to scoop up the GOP standard, then she will be stuck in Anchorage or Juneau or whatever the hell the capital is with her legal bills and her governorship, which is just another way of saying that she will be fucked.
In short, her decision is a no-brainer. There is nothing cunning or complicated or mysterious or mavericky or whacky about it.
Of course it would be nice if she would just say that. "Here are the numbers, people. The fact is, I can't afford to be your governor. I really wish I could, but life's life and I got bills to pay." But she won't, because her mystique just now comes from being crazily unpredictable, in much the way that Frank Sinatra's mystique came from his association with the Mob.
Of course there was a difference. Frank Sinatra could actually sing. Sarah Palin can't do much of anything. But I suspect she knows that, and knows that she's in over her head, and that she's got one shot, just one, to save her ass, and so she is taking it. You and I, gentle reader, would do the same. Also.
As to the Presidency, though, forget about it. America would never elect an ignorant religious whacko of grossly limited intellectual capacity to the White House. It has never been done, and it never will happen. Not even once.