Read the text description of Thomas Cromwell below from Hilary Mantel's Bring Up the Bodies.

Knowing this, he is distinguished by his courtesy, his calmness and his indefatigable attention to England's business. He is not in the habit of explaining himself. He is not in the habit of discussing his successes. But whenever good fortune has called on him, he has been there, planted on the threshold, ready to fling open the door to her timid scratch on the wood.

Why does the author use personification here? What is the author trying to accomplish?