This phrase can be a truly great pacifier when someone is upset over some rule you are required to follow but you did not invent.
For example, years ago when I was a volunteer deputy sheriff, I worked a detail in a suburb of Pittsburgh during a race.
We had to block off the main road of the suburb. Not just parts of the road, all of it. There was not a single side street I could redirect drivers to. If they wanted to cross the road, they had to wait. Quite a while, too.
Now, most people seeing a cop blocking a road can figure out he has a good reason for it. They do not demand to be let through, nor do they threaten the cop. Some may simply ask how long it would last, others just turn around, yet others wait their turn.
But then, this driver pulled up right to me and started screaming at me, threatening me, like I was some kid on a power trip who blocked the road simply because his badge let him.
Not knowing what else to tell her, I said, "Mam, I just work here." I might have shrugged my shoulders powerlessly, too.
Those words worked like magic. It suddenly dawned on her I was not the one who decided there should be the race, nor the one who should have called her before and warn her about the block.
She turned quiet, like a peaceful dove, and waited until I got the word from my Captain to let everyone through once again.