Since enough of you have asked,
-- "constant abuse" of a chest refers to opening, closing, taking items out,
putting items in, adding locks or traps, changing the labels, looking at them,
sitting on them, spilling beer on them, kicking them, hitting them with golden
arrows, and opening exploding boxes in the same room.
-- "untouched for 24 hours" refers to actual chest use. Merely walking into a
room with a chest does not "touch" it, but fiddling with the dials or hitting
it with acid arrows does.