[IMG]http://i.imgur.com/r6P8s2d.jpg
When do you expect to see ROI?

Will you see it at all ?
What is this "ROI" thing?
C
Return On Investment. The time it takes to earn back the money you have put in.
If your miner costs 1000 usd, and you earn 200 usd a month the ROI is 5 months.
Actually, you're describing "Break Even".
There's always a Return on Investment. But it can either be Positive Return (Profit), Negative Return (Loss), or Break Even (make back what you invested).
That said, I think you also missed something else here... I believe Lightfoot was being sarcastic.