Stroll the Haunted Mansion grounds, and you’ll notice a little detail on the front lawn. This strange pedestal is the Haunted Mansion sundial, with a message engraved for visiting mortals.
The sundial reads:
GROW OLD ALONG WITH ME – THE BEST IS YET TO BE
 Source: Disneyland Today
So, if you decide not to join as the 1000th happy haunt, the ghosts will settle for watching you grow old and making frequent visits.