Watch CNN's Dr. Sanjay Gupta interview Health and Human Services Secretary Kathleen Sebelius at 8 p.m. ET on Anderson Cooper 360.
Washington (CNN) -- It seems like a long time since Vice President Joe Biden whispered a bit too loudly to President Barack Obama that his imminent signing of the 2010 Affordable Care Act was "a big f---ing deal."
Biden was right -- it was big then, and is even bigger more than three years later. However, most of the talk today is about problems with Obama's signature health care reforms that are emboldening hyper-partisan critics on the political right and raising public doubts about the system's viability.
How could it be that the administration, with so much time to implement the overhaul the health insurance overhaul, ended up botching the roll out of the most controversial provision -- the individual mandate requiring people to obtain coverage or face a fine.
Some reasons are political and others are technical, but all point to a mix of presidential over-promising, rabid political opposition and the arcane contracting process used by the government to choose which companies got the job of devising a website enrollment system unprecedented in its size and complexity.
Here is a look at how we got here:
1) Water drop torture
The health care reforms were signed into law more than three years ago, so why are we still fixated on their implementation? Because of the incremental process of starting up the vast program intended to expand health coverage to tens of millions of uninsured people.
It was never going to be easy, but waiting for the system to come into full operation made it more vulnerable to a negative reaction.
Now Republican critics wonder how the administration could get it so wrong after having so much time to prepare.
"God only knows how much money they've spent and it's a failure," Senate GOP leader Mitch McConnell said Sunday on the CBS program "Face the Nation." "You know, the government simply isn't going to be able to get this job done correctly."
Obama said Monday that "the essence of the law" -- aimed at providing access to health insurance for the roughly 48 million Americans without it -- "is working just fine."
"In some cases, actually, it's exceeding expectations. The prices are lower than expected, and the choice is greater than we expected," he said of the market exchanges that came on line on October 1.
The problem, he said, was "the website that's supposed to make it easy to apply for and purchase the insurance is not working the way it should for everybody."
"There's no sugarcoating it. The website has been too slow. People are getting stuck during the application process," Obama continued, taking a shot at the law's critics by adding: "It's time for folks to stop rooting for its failure, because hard working middle-class families are rooting for its success."
2) Website woes
There are problems -- major ones -- with Healthcare.gov. While initial difficulties in logging in appear to be easing, tech experts say the use of multiple contractors to develop different aspects of the system appears to have resulted in a lack of compatibility between the different components.
A former member of Obama's technology team said Healthcare.gov was created by a "sloppy" team of contractors who were selected through a flawed federal procurement process.
Clay Johnson, who served for six months as a Presidential Innovation Fellow beginning in August 2012, wrote in a blog post on October 7 that signs of flaws on the website were apparent from the day it went online, including the use of placeholder text in the site's code.
In an interview with CNN, Johnson said the federal government is increasingly relying on a shrinking list of preferred contractors for its technology work in a process that is producing lackluster outcomes.
"There's been a consolidation of incumbent vendors and they've gotten lazy as a result," Johnson told CNN. "They haven't kept up with the market."
On Tuesday, the Washington Post reported that a trial run of Healthcare.gov days before its launch crashed the site with a just a few hundred users online.
Despite the problems, federal health officials proceeded with the planned rollout, according to the newspaper.
The result? The website crashed shortly after midnight as several thousand people tried to start the process, two people familiar with the project told the Post.
Later this week, three of the contractors responsible for the website - CGI, Serco, and Equifax -- will testify before a congressional committee about problems on the site.
In a statement, CGI said it and other contractors "are working around the clock for the improvement of HealthCare.gov, a system that is complex, ambitious and unprecedented."
Like he did with the Gulf oil spill, Obama has brought in outside experts in a move labeled a "tech surge" to try to assist in fixing the website problems.
On Tuesday, the White House said that Jeff Zients, the former acting director of the Office of Management and Budget, is part of the team of technical expert helping the Department of Health andHuman Services manage the process.
This time, though, the problem is the result of his administration's planning and implementation, rather than a private company.
The Republican National Committee challenged the government "tech surge," saying in a statement that it was "code for 'spending surge,' and will waste hundreds of millions of unbudgeted taxpayer dollars."
3) We knew this was coming
Big start-ups always have problems, White House spokesman Jay Carney has said more than once in recent days, so no one should have expected the Obamacare rollout to occur without some glitches.
However, the scope of the problems has been more comprehensive than expected, with people using Healthcare.gov facing lengthy delays or getting blocked from completing the process of signing up for the new exchanges.
In addition, insurance companies that provide coverage say they are getting incomplete customer information and duplicate applications from the system.
The White House also indicated a larger-than-expected number of visitors to Healthcae.gov exacerbated problems in the software.
While Obama called the problems inexcusable, he said several hundred thousand people have managed to sign up. While that's a large number, it's only a fraction of the 48 million uninsured and 20 million who have visited HealthCare.gov.
Carney shrugged off the issue of whether the website was ready for full action on October 1, telling reporters Tuesday that "we never said, or would have said, or would have predicted that we'd get millions of people on the first day."
4) GOP attack dog
The political origins of the Affordable Care Act of 2010 left it vulnerable to partisan attacks. It was passed by Democrats in the House and Senate with no Republican support, and GOP opponents continued to attack it in the following three years.
Conservatives consider the health care reforms the most severe example of big government overreach, and they know it will boost Democratic support from millions of people able to purchase health insurance for the first time due the reforms.
It is no coincidence that the strongest Republican effort to derail Obamacare is occurring as the most controversial aspect of the reforms takes effect -- the individual mandate to purchase health insurance by March 31 or face a fine.
Never mind that the Supreme Court upheld the law last year -- Republicans remain intent on dismantling it in any way possible, including claims about its problems that are sensational and sometimes outright false.
For example, the website Politicfact.com ruled that leading Obamacare opponent Sen. Ted Cruz of Texas spoke falsely last week when he claimed that the health care reforms meant higher premiums for "virtually every person" in America. Factcheck.org said Cruz "distorted the impact of the Affordable Care Act" on senior citizens and disabled children.
Obama opened himself to some of the GOP criticism in his zealous campaigning for health care reforms dating back to his first election campaign and continuing through the legislative battle to get the Affordable Care Act passed.
In particular, Republicans cite his frequent line that "if you like your insurance, you can keep it," noting that some employers have changed or dropped providers due to the reforms, making their workers take on new programs or seek their own coverage.
Escalating Republican attacks in recent week seek to depict chaos and long-term harm for Obamacare, but the strategy may have backfired.
By adding demands to dismantle or defund Obamacare to a spending plan needed to prevent a government shutdown, House Republicans made themselves vulnerable to blame when Obama rejected the move and the government actually started shutting down.
The shutdown began on October 1, the same day as Healthcare.gov came on line, and the political debate focused on the congressional dysfunction instead of the early reports of major problems encountered by people trying to log in to purchase health insurance.
In the 16 days until last week's agreement to reopen the government and raise the debt ceiling to avoid a possible U.S. default, polls indicated support for Obama and the health care reforms holding steady or even ticking up, while Republicans got blamed for the troubles caused by the brinksmanship and shutdown.
Now Republicans are trying to make up for the lost opportunity by hammering harder on the website woes as a reflection of the overall inability to implement and manage Obamacare.
A new CBS News poll released Tuesday showed that just 12% of respondents think the process is going well, with nearly half saying it's not going well. And an ABC News/Washington Post poll released Monday showed that 56% of those questioned said the website failures are a sign of broader problems to come.
CNN's Leigh Ann Caldwell, Paul Steinhauser, Ed Payne, Matt Smith and Ashley Killough contributed to this report.