I had no idea, and it sounds like I am not alone. I have never had a pre-revival Lilly Pulitzer garment, and did not quite understand what was so appealing. Some of these are droolworthy!
https://www.wmagazine.com/story/suzie-zuzek-lilly-pulitzer-cooper-hewitt-rizzoli-book/
https://www.wmagazine.com/story/suzie-zuzek-lilly-pulitzer-cooper-hewitt-rizzoli-book/