What finally motivates Ariana to sell her artwork?

In the story, it is mentioned that Ariana is motivated to sell her artwork to raise funds for a cause that is close to her heart. She realizes that her art can serve a greater purpose and make a positive impact in the world. By selling her artwork, she can contribute to a cause she believes in and use her talent to make a difference. The exact cause that motivates her is not specified in the context.