Key mappings

Sometimes, I think people go out of their way to create key mappings that are silly, stupid, and whatever.

  • Why is irssi's "Ctrl-K" a key combination to delete a whole line, when "Ctrl-J", with J being right next to K, is a key combination to confirm the same line?
  • Why is mutt's "x" a command to leave a folder without saving changes, while "c" is a command to leave a folder with saving changes?
  • Why did the mac designers position the "eject" key right above backspace—the second most often used key on a keyboard?

Please, pretty please, with sugar on top: make sure accidentally mishitting a key in any application doesn't perform the opposite of what one would assume it would do. Thanks.