You've probably seen experiments where a mouse gets cheese as a reward for pulling a lever. If he or she receives the cheese right away, the brain associates work (pulling the lever) with reward (the cheese) and it motivates the mouse. They want to do more work. It improves job satisfaction.
If the mouse received the cheese a month later, the brain won't associate the work with the reward. A year later? Fuggedaboutit!
Now imagine you are a software developer, operations engineer, or system administrator working on a software project. The software is released every 6 months. The hard work you do gets a reward every 6 months. Your brain isn't going to associate the two.
Now imagine monthly or weekly releases. The interval between work and reward is improved. The association is stronger. Motivation and job satisfaction goes up.
Now imagine using a continuous build/test system. You see the results of your work in the form of "test: pass" or "test: fail". Instant gratification.
Now imagine using a continuous deploy system. Every change results in a battery of tests which, if they pass, results in the software being launched into production. The interval is reduced to hours, possibly minutes.
I think that's pretty cool.