In other news

Apparently, it is not just for pets anymore!
"Intermittent reinforcement can be used once your pet has reliably learned the behavior. At first, you may reward him with the treat three times out of four, then about half the time, then about a third of the time and so forth, until you're only rewarding him occasionally with the treat. Continue to praise him every time, although once he's learned the behavior, the praise can be less effusive - a quiet, but positive, "Good boy." Use a variable schedule of reinforcement, so he doesn't catch on that he only has to respond every other time. Your pet will learn that if he keeps responding, eventually he'll get what he wants. If you have a dog who barks until you reward him by paying attention to him, you've seen the power of intermittent reinforcement."
Now I am told that some men use this in their relationships as well!
Instead of having to be consistently nice, they only have to be nice 3 times out of 4, then half the time, then a third of the time and so on. Eventually, very rarely is niceness required in your newly trained woman.