I was quite timid about registering for such an intimidating challenge. What won me over was realizing that my birthday was on the same weekend, and I couldn't remember what I did for most of my previous birthdays. (To say nothing of the other 364 days.)
After the first year, I swore I would never do such a thing again. It was a while before the psychic wounds scarred over and the nagging sense of "unfinished business" convinced me to sign up for another round, once more with much trepidation.
I am firmly in "never again" mode now....