A deadline can punish someone for waiting on a decision made elsewhere.

Deadlines assume the person can act. Often they cannot, because the thing they need is a decision, a document, or a signature sitting with somebody else. The clock runs on them anyway, and the penalty lands where the delay did not originate. The rule looks like a test of responsibility and is functioning as a tax on being dependent on another party.

When you are waiting on someone else, write down the date you asked and keep asking in a way that leaves a record. When you set deadlines for other people, ask what they need from you in order to meet them and whether your own timeline permits it. A deadline is only fair when the person subject to it holds the levers.