I think most people are thrown off by the difficulty increase percentages that people are throwing around. They are assuming a 20% raise every single time. This gives too much weight on the principle of compound interest. All you need is for one block to remain even or decrease in value to throw off the percentages for the long run. For example:

Compounding difficulty increase:
 1,418,481,395.00
 1,702,177,674.00 - 20%
 2,042,613,208.80 - 20%
 2,451,135,850.56 - 20%
 2,941,363,020.67 - 20%
 3,529,635,624.81 - 20%
 4,235,562,749.77 - 20%
 5,082,675,299.72 - 20%
 6,099,210,359.67 - 20%
 7,319,052,431.60 - 20%

With one breakeven period
 1,418,481,395.00 - 20%
 1,702,177,674.00 - 20%
 2,042,613,208.80 - 20%
2,042,613,208.80 - 0%
 2,451,135,850.56 - 20%
 2,941,363,020.67 - 20%
 3,529,635,624.81 - 20%
 4,235,562,749.77 - 20%
 5,082,675,299.72 - 20%
 6,099,210,359.67 - 20%

I think this is what most people that are buying ASIC's are betting on happening. Especially here in the first quarter of '14.