Are Women Just Not Wanting the Top Bank Jobs?

I chatted with a girlfriend who has one of the top jobs at a Canadian bank, working alongside the head of one of the top 5 executives. She is late forties and she told me she is going to switch to being a professor at a university even though she was being primed to run a large division of the bank. I was struck by what she said:

"Putting aside the family and all that - this is a decision I've made not around family. I don't want to use that as an excuse. I just do not want that level of responsibility as I do not have the energy."

It does take extraordinary dedication of time and your life to be head of a bank division. The big banks are demanding that women get hired into senior positions but the stats show that the women turnover is far greater. There are many women who run their own companies which is an altogether different scale from running one of the big bank divisions. Is my friend articulating what many women (and maybe men) realize - that they prefer more balance than giving all to the big bank career?