The magic of hard deadlines.
Soft deadlines can be ignored. They can be rationalised against and pushed back further indefinitely.
Hard deadlines are different. You can't mess with them.
They could be set either because there is a human being waiting for the work on the other end or a system that doesn't allow any slack.
In the absence of these, we can use tools like Beeminder and Boss as a Service to help us stay on the hook and make progress towards our goals.
Hard deadlines are scary but they work.