Why is Higgins interested in Eliza?

Higgins is interested in Eliza because he sees her as a challenge to transform from a common flower girl into a refined lady, showcasing his skills as a phonetics expert. Eliza's transformation also presents an opportunity for him to test his theories on language and social class. Additionally, Higgins is likely intrigued by Eliza's determination and spirit, which adds an element of excitement to his project.