Shouldn't users start with zero rep? Shouldn't every single point be earned?
What is the reasoning behind starting off every user with a little rep, then making sure that they can't ever go below that?
It's explained here.
The StackOverflow team believes that everybody's special in their own way and doesn't deserve to have a negative self-esteem (aka reputation).
A rep of zero or negative seemed cruel. Plus, everyone starts out as "a one" instead of "a zero".