Show HN: Jquery.checkbox-all.js “Enable one checkbox to toggle a whole group”

The example worked very different than what I had expected.

When I checked "All", the other boxes became unchecked, and when I unchecked "All", the other boxes became selected.

I expected the opposite behavior: when I check "All", I expect that the other boxes will be checked. When I uncheck "all", I expect that the other boxes will be unchecked.