You either hit the deadline well in advance, in which case you can sit on your hands and still consider it a victory. Or you miss the deadline and you have failed and might as well give up. Or -- the worst case -- you can tell far in advance that you will miss so you don't even bother.
Compounding the problem is that we often aren't even in full control of what can make or break the deadline, so it becomes a lottery that, whatever the outcome, awards us with an excuse to stop working.
It's valuable to know the cost of time, though. There ought to be better technologies for this than deadlines.
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I've tried to think of ways to quantify this but not arrived at anything useful. The best method I know is to explain to an expert that "I didn't ship today because the product is still missing X which is necessary for the customer because Y", and then the expert can tell you off if you're wrong.
In fact, you might get far even when striking out the expert. An "I didn't ship today because" journal might be useful on its own.
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In contrast to other comments here, I don't think this is really about people needing different sorts of motivation, but more about excplicating the cost structure of the trade-off people make when they trade time (delay shipping) for... something else. This is a hidden cost which I believe frequently is larger than people think.
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And of course, time itself is an abstraction here for the benefits one get from shipping earlier, like faster feedback, less variability in release size, etc.