I double-checked, and this phrase does seem to have originated in the excellent videogame “Portal”. Basically, it means that the reward that has been dangled in front of you was never going to be there for you when you reached the “goal”.
I saw the phrase this morning in this excellent post by Sarah Hoyt. It is as fine a summation of our current situation as I have seen. Read the whole thing.
When I clicked over to her post, I was thinking of something a colleague of mine told me a few weeks ago. There used to be a “cupcake index”: the manufacturers of cupcake paper could identify economic downturns by an uptick in the use of their product. People were baking cupcakes in lieu of… cakes. It was a kind of a belt-tightening measure. This is consistent with economics: when income goes down, demand for “inferior” goods goes up. If you can’t afford cake, but you still want to celebrate something, you substitute cupcakes for the cake.
Which, by the way, explains why the prices for used clothing at Good Will have gone up.