Last month, Disney announced to shareholders that following the disappointing returns on the expensive sci-fi epic 'John Carter', they were estimating a whopping $200 million loss in earnings.  Earlier this morning, Walt Disney Studios Chairman Rich Ross sent an e-mail to employees notifying them that he would "step down" from his post, effective immediately.

The $200 million loss on 'John Carter' was surely the most notable blemish on Ross' tenure at Disney, but it certainly wasn't just that film that did him in.  Last year, the expensive motion-capture animated film 'Mars Needs Moms' resulted in a $100+ million write-off.  And though no one would categorize it as a "bomb," much hope (and money) was behind 'Tron: Legacy' which instead became a critical and commercial disappointment.

Even when Disney films made a considerable amount of money (see: 'Pirates of the Caribbean: On Stranger Tides' and 'Alice in Wonderland'), they were often considered creative failures. And the studio is only producing one more in-house live-action film this year; the small family film, 'The Odd Life of Timothy Green'.

Disney had wisely played hardball with some productions as of late, like slashing the budget on the expensive 'Lone Ranger' reboot with Johnny Depp, but it was too little, too late, and something that should've been done with 'John Carter' long before it cost $275 million to make.

As Chairman, Ross oversaw the films from Disney, Pixar and Marvel, putting him right in the cross hairs following a string of disappointing projects.  And not even the upcoming blockbuster opening of 'The Avengers' was enough to save him (that was developed separately at Marvel Studios).

UPDATE: In an interesting turn of events, Kevin Feige, head of Marvel Studios (which is, in turn, owned by Disney) and producer of all the recent Marvel movies, is the frontrunner to take over the position vacated by Ross.

More From ScreenCrush