As soon as one deadline is met, another is looming. We work, achieve, and perhaps fail a few times, but then work and achieve some more.
What we don't tend to do is celebrate. After all, there's always more to do. Who has time for even a small celebration?
Even if it is simply a celebratory cup of coffee at some place away from the office, we should do something to note the moment.
I've got to start following my own advice.