The term 'Lay down Sally' was coined during the 2004 Olympics when olympic rower Sally Robbins dropped her oar, allowing it to drag in the water. She gave up and laid back on teammate Julia Wilson's lap. Australia consequently finished last.

Since this event a 'Lay down Sally' has been used to described someone who gives up on a job/task right in the middle of it because they can't be bothered finishing.
Dan: I'm tired of moving these bricks

John: Don't you pull a Lay down Sally on me
by Ellpup November 20, 2013
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