In fact you seem to be saying she did not do a good job yourself as you put this defense of "ceo can't do much and this ceo had bad luck"
So what has she done to earn $55 million dollars? Without attacking anything about her personally, in the role of her job, did she do a good or bad job? I think a bad job or at most neutral job. In fact in writing this comment I looked at her bio and I came away really impressed, but at the same time Yahoos stack ranking wasn't popular, Tumblr I think was a fail move. Do I think anyone could have done a better job then her? I don't know...digital ad sales is huge but as a single person I don't know how much impact you can have.
Could they not have found someone else to go down with the ship for less then $55 million (say $5 million) or is 50 million just so little money for a large company like Yahoo that people who offer hire ceo just don't give a fuck about the difference between the two numbers.