From the Lawrence J. Quirk bio of Joan Crawford: It was around this time that director Joshua Logan realized that Joan would be perfect for Norman Krasna's Broadway show "Kind Sir". He sent Joan the script; she told him she loved the play and was interested in starring in it. According to Logan, Joan insisted on a special audition in which she would read an act or two so that she and Logan would both be assured that she had the proper projection for the theater. Logan thought that Joan's audition was absolutely wonderful, and wanted to sign her for the role that very moment. As Logan told the story, Joan informed him that she had never been serious about appearing in "Kind Sir", but simply wanted to know, as he put it, "whether or not I could do it, for my own satisfaction." She told him that she could never do a long-running play because she would be "bored to death. But thank you for letting me make the experiment"
Joan told a different story that she wasn't that crazy about the play (which became the Ingrid Bergman/Cary Grant movie "Indiscreet") but since movie offers were drying up she thought Broadway might be an option. However, Joan found Logan too flattering and eager to use her name for box office and was afraid that he wouldn't give her the attention and strong direction she needed to be really excellent.
There was even an announcement in the NY Times on August 12, 1952 that Crawford and Boyer were being sought to star in "Kind Sir" but Mary Martin ended up playing the role with Boyer.