It was never supposed to.  This whole concept of making big bucks is only an artifact of ASICS and is trending towards zero from the massive gains made by those with Avalon G1's and the lucky few who got Avalon B2's in Bitsyncom's "test" shipment.  In 2012 I had an 8GH/s GPU farm which pulled ~5.5kW.  This farm made me ~5BTC/day at its peak which was equivalent to $30 a day after power was paid for.  We're almost back there (thankfully).