Peggy Noonan comes clean
 

"She went on the trail a sensation but demonstrated in the ensuing
months that she was not ready to go national and in fact never would
be. She was hungry, loved politics, had charm and energy, loved
walking onto the stage, waving and doing the stump speech. All good.
But she was not thoughtful. She was a gifted retail politician who
displayed the disadvantages of being born into a point of view (in her
case a form of conservatism; elsewhere and in other circumstances, it
could have been a form of liberalism) and swallowing it whole: She
never learned how the other sides think, or why."

"In television interviews she was out of her depth in a shallow pool.
She was limited in her ability to explain and defend her positions,
and sometimes in knowing them. She couldn't say what she read because
she didn't read anything. She was utterly unconcerned by all this and
seemed in fact rather proud of it: It was evidence of her
authenticity. She experienced criticism as both partisan and cruel
because she could see no truth in any of it. She wasn't thoughtful
enough to know she wasn't thoughtful enough."