Images via The Hollywood Gossip
I think it takes guts to do this because of the scrutiny they very well know they will have to face by baring it for everyone to see, the way it really is in real life. It's difficult for us non-famous girls to do, so imagine the intimidation celebrities must feel! To go from a face that everyone recognizes, with makeup on, to almost being completely unrecognizable just because they're showing themselves as they really are, that's brave. It says they are willing to admit that they are just like everyone else, and also the magic that makeup does in fixing their flaws.
Everyone's got something they rather hide under makeup or fix with a flat iron but underneath it all we're all imperfect flesh susceptible to break outs, split ends, oily t-zones and dark circles. That's kind of comforting in a way :) As are the words of Audrey Hepburn about beauty.