Selling an artwork is not just the only way to tap its value. If you want to retain possession of a piece but need to generate cash from it, you can simply use it as collateral for a loan. Borrowers have varying reasons for taking an art-backed loan.
Commonly, loans secured by artworks are used to keep cash flowing in a new business, cover an unexpected need, or buy more art. But ultimately, most have taken this type of loan because it's convenient and practical.