According to Chapter 16, why is the Guru considered more generous than a wish-fulfilling gem?

Chapter 16 draws a powerful distinction to highlight the unparalleled generosity of the Guru. It states that a wish-fulfilling gem, or Chintamani, is limited; it can only give a person what they can think of or desire. The Sadguru, however, transcends this limitation. As the text wonderfully puts it, the Guru gives the 'Unthinkable Object,' which is Brahman, to His devotee. This act is described as a great wonder and establishes the Guru as the ultimate refuge and the most generous giver in all three worlds. This comparison from Chapter 16 serves to elevate the spiritual gift of the Guru above any conceivable material or mental gain.