underpants gnome

Meaning

Noun

• Someone who makes incomplete plans with missing steps; someone who plans unsuccessfully.
• A plan with missing steps; an incomplete plan.

Origin

• Named for the Underpants Gnomes, characters in the South Park episode Gnomes (1998), who stole underpants from children as part of a plan to gain profit out of this activity, but their plan lacked the means by which that profit was to be made.