For your information,calculate the profit with 100BTC first in their profit calculator.You will get 0.32 BTC profit per day.So it's not impossible to make 0.32 BTC profit against 100X640 BTC=$64000.Profit is small compared to capital.But still it's profit.
Most miners struggle to ever earn enough coins to pay for their hardware.
At Cryptory, you can deposit 100 BTC, they buy mining hardware with it, and over the next 300 or so days you earn 0.32 BTC per day. After a little over 600 days your hardware has paid for itself!
That's pretty amazing - you've broken even in less than a year.
But wait - it gets better. You can then withdraw your original 100 BTC. Presumably Cryptory sells your 100 BTC mining rig, that has been working flat out for almost a year, and is a year out of date, and they magically get the full purchase price for it and send it to you. Instantly.
So your magic mining rig not only paid for itself in 300 days, you were then able to sell it for its original purchase price. You've doubled your money!
That sounds
almost too good to be true, doesn't it?