As I noted before, she was never at the senior VP level at Google (i.e. reporting to the CEO). So she just didn't have enough experience at that level.
It seems like she got the CEO job based on name recognition, and not a track record of leadership and business acumen.
It's interesting to consider the outrage about CEO pay in light of this. Sure, there are plenty of shitty CEOs who don't deserve their compensation. But you have to respect the fact that, at this level, if you aren't sharp, you'll be fleeced by your peers (i.e. De Castro, and whoever negotiated the Mozilla deal). You don't want to work for a CEO who is getting the short end of the stick all the time.
In addition to Steve Jobs' talents as a product person, he also never got the short end of any deal. (I'm saying that as a person who has never really used Apple products.) I was astounded that he basically did a reverse takeover of TWO COMPANIES -- Apple when he returned, and Disney via Pixar. He negotiated with all the thugs in the movie and music businesses. There aren't many tech CEOs who can do that.
I forget where, but I recall some anecdotes about being on the other side of the table with Bob Iger... saying that those guys basically threatened to physically harm you, and that their threats were actually credible!!! Like you should be scared for your life when messing with those guys :)