Ban appeals do work, but they are situation dependent, on what you were banned for and the severity of the offense. If you had been an active member for a year, but broke a bunch of rules because you were stressed out and having a bad day, you may be unbanned after reflecting for an appropriate amount of time if you can demonstrate you understand what you did wrong and how you'll avoid doing that again in the future. If you were banned for copy and pasting, spamming for the purpose of a signature ad, or something similar, you are out of luck.