Keep in mind that it can make a lot of sense to mine "at a loss" for now if you are holding your coins.
It never makes sense to mine at a loss, you'll get more coins for the same money by switching your equipment off and buying the coins on an exchange instead.
Ya think?
Let me give you an example. If you mined BTC right now at exactly $500 USD trade value and earned one BTC but it costs you $10 in electricity. But then held it for a month until BTC goes back up to $650 did you not come out $140 ahead?
In this example you saved $10 in electricity while I made $140 for a difference of $150. I can still buy/sell coins also while mining.
It's all a personal choice of course. But if your speculation of the coin says it's going to increase in value then it can certainly make sense to mine at a loss TODAY for higher value TOMORROW as the example above shows.
Carlo