Every time the government hires a group of people to do X, that automatically creates a class of people who:
1. Depend on the government continuing to do X for their livelihoods
2. Are experts in X and know far more about it than any government official
This creates an automatic constituency that will fight tooth and nail to keep X going no matter what. And step one of that fighting will be to make sure that the official report answering the original research question "Did X work?" will never be a clear "No."
And God help any politician that ignores the official report and cancels X anyway. Now the problem that X was intended to solve is entirely their fault, and there's an army of X experts running to every media outlet in the country making sure the general public knows it!