No, I'm saying that in order to get the $15 million there has to be some sort of measures in place to make sure that people don't game the system. If you just give them $15 million with no strings attached, they might decide to do the bare minimum and pocket the rest.
Maybe you could stipulate that each company has to meet a minimum bar in order to get that $15 million. Maybe advance some of the money up front, then pay the rest if they meet the bar. If they fail to meet the bar, they have to give back some of the money.
In any system you implement you need to give a lot of consideration to how someone might abuse the system because someone absolutely is going to at some point.
I didn't expect it was necessary to spell out the details of the arrangement to support the validity of the approach. The purpose of the suggestion is to approach the problem differently to achieve a successful outcome.
Administering this type of procurement arrangement, while certainly important to all the points you have raised, has very little to do with the success of building and delivering healthcare.gov.
Maybe you could stipulate that each company has to meet a minimum bar in order to get that $15 million. Maybe advance some of the money up front, then pay the rest if they meet the bar. If they fail to meet the bar, they have to give back some of the money.
In any system you implement you need to give a lot of consideration to how someone might abuse the system because someone absolutely is going to at some point.