Earlier quoted context omitted.
I had managers yell at me when at the sprint review meeting we realize we were going the wrong way and decide to scrap some of the work of the last few weeks... Imagine politicians with a stake in the project's failure hearing that: they will go full Benghazi on it.
Better a few weeks than a couple of years and millions of funding.
If it's either a failed public project, or spending millions of dollars (that can be spun as creating jobs), what do you think they're going to take?