She's fragile. It has to do with the spinectomy she had just before going into politics.

she'll be involuntarily retired in 2020.

I never agreed much with Olympia, but she was a real feeling person. Collins ain’t worth much. She sort of floats in an ocean without any true beliefs except how can I float longer.

She is a large part of the reason Trump has carte blanche to do what he is doing. Her votes, along with several other "GOP moderates" were the crucial votes for legislation like the tax bill fraud and Kavanaugh. You can put Flake in this category also.