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The two situations aren't comparable though. Money in a bank account just sits there and collects interest. Money put into a Bitcoin mining rig requires constant fussing with; you need to upgrade software as newer versions come along, keep the rig up and running through power failures, mining pool failures, potential hardware failures, and pay continual electricity bills.
Mining rigs have to pay themselves off in a manner of months. The exponentially increasing difficulty level means that any rig will output most of its lifetime Bitcoins (>90%) within the first few months. After that it's just peanuts. So talking about it on a scale of ten years is meaningless. Besides, there isn't a mining rig that exists today that will be worth running anything close to ten years from now. New hardware will come along that is more efficient in terms of electricity used and will make anything we're running today not even profitable to run for mining within a few years.