PS Call me an idiot but I would have not dare buying USD 14400 worth of bitcoins at the time, so from MY perspective I did very well buying the miners...
I am not implying you are an idiot, I also purchases a Jupiter and still hope it will have positive BTC ROI. What you need to realize is that you DID invest 14400USD in bitcoins. You invested that money in the BTC you predicted those miners to make. If the exchange rate had crashed you would have lost even if the Jupiters made positive BTC ROI. Nobody would buy your Jupiters for much if BTC was trading at $10. Investing in a miner has the ADDED risk of increasing difficulty and shipping delays so it was a higher risk than investing directly which is only effected by the exchange rate.
I understand completely what you are saying and I'm just pointing out that this statement is false:
If it mines less bitcoins than you have paid for it (or that you could have bought when you paid for the machine), then you did bad.
It's not bad, it's just worse. There is a difference

I don't think you understand that many people paid in BTC...not fiat. Many people DO NOT cash out to fiat (or buy BTC). If you don't make back the BTC you spent, you've lost something....that is a bad investment.
Exactly, I am in it for the long haul and have only ever invested BTC that I have mined starting with the GPU era and am only interested in increasing my BTC holdings so the exchange rate means very little to me. I understand why people get excited to make a fiat profit but I just want them to realize when it was not because of investing in mining but because they invested in BTC via mining so that they don't continue to purchase miners that ultimately reduce that fiat profit.