Diane Arbus's photographs are more about her inner psychological workings than her subjects. She reportedly manipulated the subjects until she found the look she was looking for.... She would put her feelings into the images. She would manipulate, intimidate and coerce the subjects until she got what she wanted. Perhaps not in all her photographs, but she clearly used this technique on a large number of her subjects. For a detailed account of her inner workings I would recommend the book Emergency in Slow Motion: The inner life of Diane Arbus by William Schultz.
[http://www.lensschool.com/blog/diane-arbus]