Not exactly what you think.  The fact is that during the time while you pay off the costs of mining equipment, firstly, it becomes outdated and can break down (by the way, all decent farms have repair departments that work constantly), and secondly, the price of mining in dollars is highly volatile and these 12  months can turn into 36 (for example), in the third, each project has a "life span", beyond which nothing can be earned.  In short, the case may turn out risky, but most likely it will not work.