What makes a fire burn is space between the logs, a breathing space. Too much of a good thing, too many logs packed in too tight can douse the flames almost as surely as a pail of water would. So building fires requires attention to the spaces in between, as much as to the wood.
When we are able to build open spaces in the same way we have learned to pile on the logs, then we can come to see how it is fuel, and absence of the fuel together, that make fire possible.
We only need to lay a log lightly from time to time. A fire grows simply because the space is there, with openings in which the flame that knows just how it wants to burn can find its way.