Consider how even if you try to optimize the costs the projects get cut down until the rationale for cost optimization disappears, like with Cassini-Huygens whe

Consider how even if you try to optimize the costs the projects get cut down until the rationale for cost optimization disappears, like with Cassini-Huygens where a promising serial production drone body for handling unmanned missions was effectively canceled. At least with manned missions it's easier to drum up popular support or play on politicians' ego about being without a manned capability.