As opposed to an ArtificialDeadline; a Real Deadline is one that really matters from a business perspective (i.e., profitability, competitiveness, contract commitments, etc.).
Some deadlines should be ignored or at least mitigated (but not to the point that your job is at risk). These are the ArtificialDeadlines. The real ones should be respected. Sometimes the difference between the two is not so obvious.
Real Deadlines:
See QuadrantOne vs QuadrantThree of the FourQuadrants