From its root words, "deadline" essentially means if you cross the line, you're dead. Now, deadlines, mind you, are part of everyday professional life. They are the most prominent features of the ongoing wheel of economy and business, where everybody wants everything done how, where, when, and most importantly by what time.
I always hated when people promised fulfilling deadlines to superiors when there are too many external factors to the equation, when they are not too sure their subordinates can help make that deadline, or whatever reason. Deadlines are made for performance and to push performance, but I don't think deadlines are meant to leave out maintaining the long term performance.
The current business scene moves at such a pace where things often go too fast for the people actually doing the work, and thus having to stay back at the office (or any other place of work) toiling the hours away.
It's not that I don't like deadlines; they are necessary milestones to measure your performance and accomplishments.... but they are, at times, unnecessarily issued as well.
Here's hoping the deadline met meant something.