It's interesting to look back at older posts in the forum such as those from 2011 or 2012 where newbies ask about mining and even back then, people said that mining was unprofitable and that you'd be better off buying them from Mt. Gox instead:
On the other hand, the exchange rate has been increasing lately. If you believe this will continue, then the numbers above don't look as bleak. However, it also means that you'd be better off purchasing BTC rather than mining hardware. If the exchange rate really does increase, your BTC will increase in value. Meanwhile, your hardware will only depreciate and produce less BTC over time...
...If you're counting on the increasing exchange rate to buoy your mining rig profitability, then you really should be investing directly in BTC, not buying mining hardware.
after some analysis and some risk models done with help of professionals back in May 2012 I have suggested to some people I've been in touch with regarding potential ASIC mining project to forget about mining and simply buy BTC instead. After that our ASIC project was scrapped. It was back when BTC was valued at 5$.
From a thread on Reddit posted 29 Feb 2012:
...I'm not sure it would be worth it at all to mine coins. You're probably a lot better off just buying them.
From a thread on Reddit posted 22 Sep 2013:
The difficulty keeps skyrocketing faster than equipment can pay for itself. So you're going to lose money investing in mining equipment at this point in time. You'd be better off simply buying bitcoins.
Obviously I'm not talking about cases where Bitcoin mining paid off because of the increase in BTC price. Someone who spends $50 mining $30 worth of BTC which later becomes worth $300 would still have been better off buying the coins instead.
I know the first generation Avalon ASICs were extremely profitable and would reach ROI in just 9 days. Has there been any other examples of periods where Bitcoin mining would have been more profitable than simply buying and holding?