When you build a fire, it burns hot and fast, and then the embers create a long, slow roast that can go on for hours. You add wood, and you stay warm for as long as you need to. When you don't add wood, slowly the fire dies down, but the embers stay good and hot. It takes quite a while for them to die by themselves, and often, campers pour water on their fires to make sure nothing is left that could start a forest fire. The great thing about those embers, though, is that if you don't want to put out your fire, you can stir them up with a stick and throw a little kindling on there, and before you know it, you've got a raging flame again.
Creativity never dies out. Sometimes you've got to let it simmer, sometimes you've got to walk away from the fire pit for a while, but come back and poke it. Then stand back or it will take your eyebrows off.