Obamacare, one of many sweeping changes the people did not get to vote on.
Many implementation problems were overlooked before signing this into law, including website malfunctions, non-intuative online and phone support, and inability to contact somebody in charge to fix problems as they happen. Should you have a problem with sign-up and also be sick, you will likely either be very miserable for a long time or have expired before problem has been resolved.
This law should have never been signed into law without first creating working, tested, procedures in every step of the process.
Reform simply doesn't happen by legislative vote and a presidental signature. Reform happens through fair and careful planning reaching towards a realistic goal.