Maybe because I'm kind of shocked to realize how beautiful (in the context of her spending most of her time as a voice actress) she was as a young woman. Here she is on I Love Lucy around 1952. She was in her 30s (and pregnant) and yet, she was playing a teenager:
gr2LIev65bU

https://images.findagrave.com/photos250/photos/2016/164/164754912_1465801293.jpg

https://alchetron.com/cdn/janet-waldo-b713be7d-20c6-475d-9cc0-1e107b65451-resize-750.jpeg

http://www.sitcomsonline.com/photopost/data/1696/1950_Press_Photo_Janet_Waldo_on_Meet_Corlis_Archer_from_Hollywood.JPG

http://www.sitcomsonline.com/photopost/data/1696/meet-corliss-archertrtrtrtrtr.JPG