It's even worse than that. Schedules slipping and cost overruns are good things for the manufacturer, because they can charge more on top of their initial contract. Cost-plus ftw.
But you still run into similar issues regardless of the contract structure. Try and build a rail network without anyone in government wanting something changed from the initial design for 20 years.
Ukraine fights back or they lose their sovereignty. Most of the conflicts the US gets into, it's entirely a choice to put soldiers at risk.
So yeah, the evaluation of war effort will be different, because the situations are completely different.
Startups = have few resources, product has to work or company dies
Big tech = minimal cost of failure, instead minimizing risk
And yet this mechanic is also why startups are able to innovate and bring new products to market so much faster.