> Next time, when someone starts a conversation about your team's estimate, pushing for a lower estimate without any new insights that will lower the effort, ask them: do you ever tell the meteorologist it isn't going to be this bad weather tomorrow?

I'm more direct. I ask them why. As in "why do you think it's less work / time / effort?". Every single time they've realised it's not less, they just _want_ it to be less.