It has been suggested that people become actors for the same reason they like extreme sports. Both have similar challenges that test one's vulnerability.
After jumping out of airplanes for a few years I discovered an adrenaline rush can also be found as an actor ... with less chance of being KILLED.
But, the ACTING challenge (for me anyway) is getting out of my own way ... giving up control to the CHARACTER so he can jump inside and become alive.
It's fun, though, when he CUSSES a lot. I don't know why, but for some reason it feels good to say "#>%!" and "≠?¤#$" in front of a lot of people - and not get in trouble for it.