File this one under "O" for "Oops." A cleaner with the best intentions accidentally destroyed a piece of art worth more than $1 million when she removed what she thought was a "stain" from the installation. Spoiler alert: It wasn't really a stain.

The piece of art, titled "When It Starts Dripping From The Ceilings," features a series of wooden planks and a (formerly) discolored plastic bowl. The artist, the late Martin Kippenberger, intended for viewers to understand that the bowl had been discolored by water running over the pieces of wood.