I think the problem is that too many people in government and science believe in the "noble lie". "Yes, we don't actually believe our prediction, but what does

I think the problem is that too many people in government and science believe in the "noble lie". "Yes, we don't actually believe our prediction, but what does it matter if it's exaggerated? We're doing it in the name of XXX which is a great cause." Sadly, when those predictions fail to materialise, they become the science equivalent of the Boy who Cried Wolf.