It strikes me that if you compare writing with house building, then you have to remember that a new building involves a lot of planning beforehand. AS far as possible, the builder follows the plan. However, the builder may come across an obstacle which requires a change in the plan.
What also comes to my mind is that prior to starting a new building, you have to clear away what is there already. Before you start to build up a house (brick by brick, as you say), you first have to dig down and prepare the foundations.
So if you consider the actual writing of the story to be the bricks, then the foundations musty represent the research which goes beforehand. Clearing away the ground might be analogous to editing and rejecting ideas.
Hmm, well that’s my two cents worth.