Why do people think centuries end one year before they do?

[FragilE^]

I don't give too much importance to any year, simply because the earth does not know nor does it care about when we decided year 0 was. Same with "Friday the 13th" and stuff like that.

More on topic though, no, I didn't know this. But I'll stick with the "wrong" system, cuz it makes more sense to me :P