couldn't organize an orgy in a brothel

rude slang (Someone) is utterly incompetent or unable to arrange things successfully; (someone) can't even manage or carry out the simplest of tasks. I'm not surprised Marie's event was a disaster—she couldn't organise an orgy in a brothel! The leaders of this country couldn't organise an orgy in a brothel, let alone overhaul the entire tax code! No wonder the strike failed. Those dipsticks couldn't organize an orgy in a brothel!