What really happens is they are saddle with tonnes of regulations (Safety-Sh*t Mostly), and constantly changing expectation and requirements from Congress and the President. Add the politicization of the agency so now there are more Admins/Managers then Engineers. But wait there is more: the fact that they can't (READ: CAN NOT) hold their contractor to timelines, deadlines, or even what the final product is, while still having to pay for overruns, redesigns and mistakes. ( I can see Lockheed running to their favorite bought-and-paid-for congressman now: "Big mean NASA wants us to deliver what we promised and what we were paid for, wah wah.")
NASA is far too valuable a resource to let Congress and the President have any say over it.