Yup.
Before buying the hardware, people should really check the profitability (there are tons of profit calculator out there), and take the uprising difficulty and electricity cost into consideration.
Even with profit calcs, it's very deceiving on what you're really going to make. I projected a 35 day return on my miners with difficulty and electricity adjustments which has now turned into 100 days thanks to the surprising rise in difficulty. You can't calculate that X factor to a solid number unless you know exactly what the thousands of other miners' circumstances are. It's just not a winning endeavor unless you get a miner for absolutely nothing...or if coin values quadruple in the next few days. Neither scenario seems likely.
Since August the increase in difficulty has been quite stable around the 25-30% mark , with a spike to 40 in late october but followed
by under 20% for the next 2 adjustments.
If you didn't take this into account , then you wasted your time with a wrong profit calculator or you get the numbers wrong.