Mining is a risky business, in the first years was very profitable ma in this period it's safer to buy btc and forget it.
In the first few year, bitcoin isn't known quite well, there wasn't much attention given to Bitcoin. People actually profited by buying used GPU and custom built some rigs. The only person that profited the most were successful mining botnet operators. The reason for mining to be profitable is that not many people believed bitcoin would succeed and did not go into bitcoin mining which did not increase the difficulty a lot, most of the believers would buy cheap machines and mine and probably hold for a while. There were a few bubbles and I could say some miners have sold their coin then and profited a lot. The game isn't all about the speed of the equipments you have but is when to sell the bitcoin so you can get the best profit, the best is probably to buy them. I have really warned people about investment to mining contracts, especially newly created sites. Mining contract can never profit and huge risk incurs with less known sites.
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