Year 11 is the primary reason. The failure actually begins with year 5, but Obama and his legislative supporters have done their best to hide the fact that years 5 through 10 of their plan are unaffordable. They think we're stupid enough to believe their ploy of starting taxes 4 years before they start providing benefits so they can claim that the overall 10-year plan is financially balanced.
Year 11 has no such camouflage: The year following the 10-year plan will cost billions of dollars more than the taxes taken in for it. Either taxes will have to be raised, the national debt will have to be raised, the benefits will have to be cut, or some combination of these actions. Regardless of what else you like or dislike about this health insurance legislation, we simply can't afford it. We can't afford it now, and the next generation can't afford it later.
We already have the same impending problems with Medicare, Medicaid, and Social Security. It's all an economy-ruining financial time-bomb. Take a look at the following chart (data from Dept. of Treasury). Medicare and Medicaid are part of the Dept. of Health and Human Services budget, and under current laws, they will continue to grow rapidly. The baby-boomers are beginning to retire and Social Security outlays will continue to grow rapidly. The astonishingly irresponsible deficit spending over the last few years (Bush 2 and Obama) will cause the interest on the national debt to continue to grow rapidly in addition to threatening the stability of the dollar.
I'd rail awhile about how all the effort toward the misguided health-insurance legislation should have been focused on the economy, as the President seemed to acknowledge in his first State of the Union address ("Creating jobs has to be our number one priority in 2010") but I have no reason to think that this President or legislature has any understanding of how to improve the job situation. For example, the President and legislature are still virtually ignoring the continuing meltdown at Fannie Mae and Freddie Mac, with extremely far-reaching consequences for the housing industry and the economy. Nevertheless, since health-insurance is in fact, still his number one priority, I'll close with a quotation from former Democratic President Bill Clinton, which I direct to the increasing egotistical President Obama:
"It's the economy, stupid."